Science Lessons and Projects

summer Science lessons and projects

1 TABLE OF CONTENTS: AMUSEMENT PARK RIDES & ACTIVITIES BUMPER CARS: NEWTON’S THREE LAWS OF MOTION...... 3 CAROUSEL: CENTRIPETAL FORCE...... 4 FREE FALL: POTENTIAL ENERGY, KINETIC ENERGY, AND GRAVITY..... 5 ROLLER COASTER: PUTTING IT ALL TOGETHER...... 6 HOW TO MAKE A ROLLER COASTER...... 7 BIOMES SEASHORE COLORING PAGE & WORKSHEET...... 8 SUMMER SCIENCE WORKSHEET...... 9 SINK OR FLOAT WORKSHEET...... 10 DESERT LIFE WORKSHEET...... 11 OCEAN ANIMALS WORKSHEET...... 12 ENERGY WHAT IS ENERGY?...... 14 TYPES OF ENERGY COLORING PAGE ...... 17 ALTERNATIVE ENERGY SOURCES...... 18 DESIGN & BUILD A SOLAR CAR...... 22 BUILD A MOUSETRAP CAR...... 24 SUMMER BUGS BEE MEMORY EXPERIMENT...... 26 SMELLING BEE ACTIVITY...... 27 LADYBUG LIFE CYCLE...... 28 MAKE A BUTTERFLY FEEDER...... 30 POND STUDY SCIENCE PROJECT...... 31 MAKE AN INSECT COLLECTION...... 32 ASTRONOMY SOLAR ENERGY MATCHING GAME...... 35 SOLAR SYSTEM COLORING PAGE...... 36 STAR CHART WORKSHEET...... 37 SUMMER STARGAZING...... 38 ASTRONOMY: PHASES OF THE MOON...... 40 4TH OF JULY MAKE 3D FIREWORKS GLASSES...... 42 FIREWORK SCIENCE...... 44 PROPERTIES OF METALS...... 45 HOMEMADE ICE CREAM IN A BAG...... 48 HOW TO MAKE A FIRE EXTINGUISHER...... 49 DISCOVER THE FLAMING COLORS OF FIREWORKS...... 50 D.I.Y. SCIENCE HOW TO MAKE QUICKSAND...... 53 HOW TO MAKE A LIGHT FOUNTAIN...... 55 HOW TO MAKE A KALEIDOSCOPE...... 56 HOW TO MAKE A MINI HOT AIR BALLOON...... 57 HOW TO MAKE A SOLAR WATER PURIFIER...... 59 NATURE SCAVENGER HUNT...... 60 SUN PRINTS...... 65 HOW TO MAKE A WATER WHEEL...... 66 2 BONUS HOW TO PLAN A SUMMER SCIENCE CAMP...... 68 Bumper Cars: Newton’s Laws of Motion Bumper cars are a great place to see Sir Isaac Newton’s three laws of motion in action. Here’s how:

1. Newton’s First Law: Every object in motion continues in motion and every object at rest continues to be at rest unless an outside force acts upon it. This is because all objects have inertia – the property of matter that resists changes to the object’s motion. © Home Science Tools. All rights reserved. Reproduction for personal or classroom use only. Newton found that if a ball is sitting on a table, it will stay sitting there because that is what it ‘wants’ to do. If the ball is set in motion, it will keep traveling in a straight path because, again, that is what it ‘wants’ to do. An object in motion will not stop, slow down, or change its direction unless an outside force acts on it (such as gravity, friction, and air resistance).

When you are riding in a bumper car and end up in a collision with another bumper car, you feel a jolt. This is because your body’s inertia wants it to keep traveling in the direction it was moving with the car even though your bumper car has now suddenly stopped.

2. Newton’s Second Law: The greater the mass of an object, the harder it is to change its speed. (More force is needed to move it.) You already know this law and practice it in your everyday life. Some- thing that is small, such as a pebble, is much easier to pick up and throw than something that is large and heavy, such as a boulder. When riding in the bumper cars, you may have noticed that people who weigh less tend to get pushed around more than people who weigh more. The more mass (weight) an object has, the more force it takes to move it. And since all the bumper cars usually have the same top velocity, the cars carrying more mass will never travel as far as the cars carrying less mass after a collision.

3. Newton’s Third Law: For every action, there is an equal and opposite reaction. If two bumper cars traveling at the same speed and carrying the same amount of weight run into each other, they will bounce off and move an equal distance away from each other. And based on the second law, if there is a difference in the amount of weight being carried in the two cars, the car with less weight will travel farther away from the point of impact than the car carrying more weight.

3 CAROUSEL: CENTRIPETAL FORCE Experiment Imagine spinning a ball on a string around you. The ball is traveling in a circular path. But Newton’s first law states that an object in motion stays in motion and that motion is in a straight path, not a circular path.

Since the ball is traveling in a circular path, an outside force must be acting on the ball – that force is the string. The string is pulling the ball back toward you, acting as the centripetal force. Centripetal means ‘center-seeking’ and is the force that is acting on © Home Science Tools. All rights reserved. Reproduction for personal or classroom use only. the carousel.

The platform upon which the horses and people are riding is the centripetal force that keeps them traveling in a circular motion just as the string was the centripetal force for the ball.

As long as the ride is moving slowly enough, the centripetal force of the platform can keep everyone and everything on board.

In theory, if the carousel starts moving really fast, centrifugal force* (‘center-fearing’) takes over and breaks the hold the platform (centripetal force) had on the riders and the riders would fly off.

*Centrifugal force is actually not a real force. If the centripetal force that pulls an object into the center stops working (e.g. the string breaks), then it is the object’s inertia that takes over and sends the object traveling in a straight path.

You can test this outside by spinning a ball around you and letting go of the string. If centrifugal force was a real force, the ball would move straight away from the center at the point where the string was let go.

But it doesn’t. Instead, the ball follows its path of inertia and moves in a straight path that is tangent to the circular path.

4 POTENTIAL& KINETIC ENERGY, & GRAVITY Science Lesson

In free fall rides, motors are used to take the car and the passengers to the top of a tower, building potential energy as they reach the top. Potential energy is stored energy and has the capability to become working energy. When the car is released, the potential energy is turned into kinetic energy (the energy of motion) as gravity pulls the car and passengers back down to the earth. However, no matter what an object weighs, all

objects fall at the same rate*. So both you and the car are falling at the same speed, © Home Science Tools. All rights reserved. Reproduction for personal or classroom use only. giving you the feeling of weightlessness.

Now you may be ‘fooled’ into thinking that the car is falling faster than it normally would if gravity was the only acting force (i.e. the ride makers are using motors to make the car fall faster). After all, you did see and feel yourself being pressed up against the bars and straps holding you in as soon as the car dropped. But remember that your body has inertia and wants to stay at rest, as does the car you are sitting in.

The mechanism suspending the car at the top of the tower is holding the car, not you. The car is holding you. So when the mechanism that is suspending the car lets go, there is a slight delay of your body falling with the car because your body’s inertia wants to keep it at rest. If the same mechanism dropped you and the car at the same time, there would be no delay of your body falling in comparison with the car.

*Although all objects do fall at the same rate no matter what their weight or size, some objects are more likely to be affected by air resistance than other objects. Because of their spherical shape, balls allow air to easily move past them, with little air resistance to slow them down. Feathers and parachutes are shaped to capture the air as they fall to the ground, effectively slowing them down. In a vacuum, all objects always fall at the same speed since there is no effect of air resistance.

5 Roller Coaster: Putting It All Together Science Lesson

Roller coasters are the perfect place to see all these laws, forces, and energies at work! Roller coasters are not powered by motors the entire way along the ride.

In fact, most roller coasters are only pulled up to the top of the first hill – the highest point of the entire ride. Its entire trip relies solely on the potential energy it has gained

by its position at the top of this hill. The higher a roller coaster climbs a hill, the greater a © Home Science Tools. All rights reserved. Reproduction for personal or classroom use only. distance there is for gravity to pull it down. When the roller coaster comes down the hill, its potential energy is converted into kinetic energy.

When the coaster moves down a hill and starts its way up a new hill, the kinetic energy changes back to potential energy until it is released again when the coaster travels down the hill it just climbed.

Gravity and inertia are big players when it comes to how you experience the ride. The force of gravity is measured in g-forces. Most of the time, you are experiencing 1 g, the normal force gravity exerts on you. However, motion can change how you experience the force of gravity. When the cars are traveling up the hills, you feel heavier because your inertia wants you to stay behind and more g-forces are exerted on you.

So, if a ride states that it exerts 3 g-forces, then you will feel like you weigh 3 times more than you really do while riding on the ride. Alternatively, when the car travels down the hills, you feel weightless because you are falling with the car and are experiencing 0 g-forces. When loops and twists are built in the track, the track becomes the centripetal force that keeps the cars and passengers moving in a circular motion. The inertia of the passengers, which wants them to travel in a straight line, makes the passengers feel like they are being ‘pressed’ into their seats while traveling through the loop. When a coaster goes up a loop or hill, it must come down, because for every action, there is an equal and opposite reaction. And if there is not enough force or speed to overcome its mass, a roller coaster cannot make its way through the entire course of its track.

6 Roller Coaster: Putting It All Together Roller Coaster: Putting It All Together Free Fall

WHAt YOu NEED: (you may not use all of these items)  Marbles  Glue  Cups  Wood Blocks  Vinyl tubing  Books  Staples  Cardboard  Tape  Metal B-Bs  Bed tubes  Staircase  Cereal boxes  Foam  Ball bearings  Clay insulation  Poster Board  Chairs tubes

Test your knowledge of physics by making your own roller coaster. You can make a roller © Home Science Tools. All rights reserved. Reproduction for personal or classroom use only. coaster out of just about anything, but below you’ll find a list of materials to use as cars, to make tracks, to support your tracks, and to make hills. You may find some materials work better together than other materials, especially depending on the size of your track and cars. WHAT YOU DO: 1. Spherical objects such as marbles and ball bearings tend to make the best “cars” for your roller coaster. The size of the marbles/balls needed depends on the type of material you use for your tracks. For instance, while vinyl tubing works well to make tracks that bend and curve, only small objects like B-Bs and ball bearings can actually fit in most vinyl tubing. However, vinyl tubing is probably the easiest material to make tracks with, so we recommend using it for your first attempt at making a roller coaster. Most hardware stores carry vinyl tubing in a variety of sizes, so test your cars to make sure they can move through it before you purchase it. 2. If you use poster board or cereal boxes, cut out long strips to make your track. You may have to build walls or sides to keep your car from falling off. Whatever material you use, build your track so that the cars can run smoothly on it – no cracks or seams that will trip up the cars. 3. Use the adhesives to connect track pieces together as well as connect the track to your support system. 4. Remember the laws and forces of motion when building your roller coaster track. Your first hill must be the tallest to build up enough potential energy to get your car through the track. Adjust hills and loops so that the car will have enough velocity to make it through the course without having so much speed that it flies off. You may want to try several different cars with different sizes and weights to see which car moves through your track the best.

WHAT HAPPENED: You may find it very tricky to build the track just right so that the car can make it all the way through without falling off. Ride makers of roller coasters face these same challenges: how to make a fun, thrilling ride that is also safe. But by following the laws of physics, ride creators can make rides both fun and safe without a lot of trial and error, which is a good thing for the riders!

8 how does earth move around the sun

The diameter of the sun is 109 times that of earth! THE SEASONS

Spring

Earth rotates at about Note: earth and 1,000 mph! the sun are not Summer Winter One rotation takes 24 hours drawn to scale. or 1 day.

Fall

(for the northern hemisphere) Earth revolves around the sun at a speed of 67,000 mph!! One complete revolution takes one year (365 days).

REVOLUTION ROTATION

9 will it sink or float? 1. Draw a picture of one item that you want to test in each box on the left. 2. In the box next to each picture, circle if you think the item will sink or float. This is your prediction. 3. Drop the object into the water and watch what happens. Was your prediction right? Circle sink or float to show what happened. This is the result of your experiment.

DRAW A PICTURE OF WHAT DO YOU THINK WHAT HAPPENED? EACH OBJECT. WILL HAPPEN?

sink sink float float

10 what lives in the desert? Draw pictures of desert plants and animals on plain white paper, then cut and paste the into the spaces below. Remember, many desert animals are nocturnal!

UNDERGROUND UNDERGROUND

11 ocean animals coloring sheet What to do: 1. Color the animals. 2. Carefully cut each one out. 3. Glue each one into the ocean on the next page. 4. Draw and color other animals to fill your ocean scene. Remember that some animals live near the bottom of the ocean, some live in the middle, and some live near the surface. Put each animal where you think it like to live. © Home Science Tools. All rights reserved. Reproduction for personal or classroom use only.

13 what is energy? Science Lesson

Energy is usually defined as ‘the ability or capacity to do work.’ Work is the transfer of energy, usually defined as force applied over distance or force x distance. Energy is measured in joules (1 newton of force applied over 1 meter distance) or foot-pounds (1 pound of force applied over 1 foot of distance). Power is the rate of doing work or transforming energy from one form to another. Power is measured in watts (1 joule per second) or horsepower (550 foot-pounds per second). So a 60 watt light bulb converts 60 joules of electrical energy per second into light and heat energy. If you lift a

box you are using energy from your body to do work. © Home Science Tools. All rights reserved. Reproduction for personal or classroom use only. Potential or Kinetic Energy The different forms of energy can be classed as either potential or kinetic. Potential energy is being stored, ready to do work. If a pencil is resting on the table, it has potential energy. If it falls from the table, that potential energy has been changed into kinetic energy, the energy of motion (with a boost from the kinetic energy of whatever gave it a push). When the pencil hits the floor, some of its kinetic energy disperses. Eventually all of the pencil’s kinetic energy is transferred to the floor and it stops rolling. Once it’s settled on the floor, it no longer has potential or kinetic energy. If you come along and move the pencil, your potential energy has been turned to kinetic energy, not the pencil’s! This transfer of energy from one form to another without changing the total amount is called the conservation of energy. This ties into the first law of thermodynamics, which states that energy cannot be created or destroyed – it can only change form. What is Energy in Science You are probably already familiar with energy called electromagnetic radiation, even if you’ve never heard the term before. Visible light, x-rays, microwaves, radio waves, and the ultraviolet radiation that gives you a sunburn are all different types of electromagnetic (EM) radiation. So what is EM radiation? Basically it’s a stream of tiny electrically-charged particles called photons, which travel in waves. They actually move in a special type of wave, called a transverse wave: one that doesn’t need a medium like air or wire to travel through. This means that EM radiation can travel through the vacuum of space. All electromagnetic waves can travel at the same speed, the speed of light, which is about 186,000 miles per second! However, they only travel at maximum speed through a vacuum; things like water and air slow them down. Transverse waves have oscillations (up and down or side to side movement) that are at right angles to the direction their energy is traveling. Since the electromagnetic spectrum is also made up of photons, it can act as either a stream of particles or as a wave. EM radiation is made of electrical fields and magnetic fields together. Each type of EM radiation has different wavelengths and frequencies. Frequency is the number of waves in a given time. The shorter the wave, the higher the frequency. And the higher the frequency, the higher the amount of energy in the wave.

14 what is energy? - page 2 Wavelength refers to the distance between each complete wave cycle (e.g., two peaks right next to each other). The sun is the source of much of the energy on this planet. Unlike the earth, the sun is not a solid; instead, it is a huge ball of gas, composed mainly of hydrogen. Every second, the tiny nuclei (plural of nucleus) of tons of atoms fuse together to form molecules. Huge amounts of energy are released in the process. This energy is in the form of electromagnetic radiation. Heat Heat energy is often transferred by infrared electromagnetic radiation. © Home Science Tools. All rights reserved. Reproduction for personal or classroom use only. It is at a wavelength invisible to our eyes, but our skin can sense it. Heat energy can only be kinetic, since it is energy of moving particles. The increased energy from the transfer makes molecules speed up. As they move faster, they bump into each other and spread out. Enough heat can break the bonds that hold molecules together as a solid, so they become a liquid. Add more heat and the liquid will become a gas. Heat moves from hot temperatures to cold temperatures. It keeps moving until all the molecules around it are the same temperature (somewhere in between the original temperatures that were mixed). This evened-out state is called thermal equilibrium. If you give a cup of oil and a cup of water an equal amount of heat, the oil will get hotter because it has a different thermal capacity – its molecules move faster. Temperature is the measure of how hot or cold something is, based on how fast or slow its molecules are moving. Two commonly used temperature scales are Celsius (C) and Fahrenheit (F). The freezing point of water is 0°on the Celsius scale and 32°on the Fahrenheit scale; its boiling point (when it turns into vapor) is 100°C and 212°F. Light Light is electromagnetic radiation in the middle of the spectrum. Its wavelengths are medium- sized, the only wavelengths that our eyes can detect. All of the colors of the rainbow are part of the visible light set of the electromagnetic spectrum. Red-colored light has the longest wavelength (just short of infrared) and violet-colored light has the shortest wavelength (just longer than ultraviolet radiation). The sun and other hot sources produce incandescent light, which is light energy converted from heat. Fireflies, glow light sticks, and fluorescent bulbs convert other kinds of energy to light without using much (or any) heat. Sound Sound travels in longitudinal waves, which requires a medium, such as air, in order to travel. These are also compressional waves, formed when air is pushed away and then clumped together with empty spaces in between. Use a slinky to demonstrate how these waves work. Have someone hold one end of the slinky, and you hold the other. Spread apart so that the slinky is stretched out to about half its length. Now push your end of the slinky straight out toward the other person. The coils of the slinky will also push forward in bunches as the ‘wave’ ripples down the length of the slinky. When these waves go through your ear and are processed in your brain, they are converted to sound that you can hear. 15 what is energy? - page 3 Chemical Chemical energy is potential energy stored in the chemical bonds that join atoms together. It can be converted to electrical, heat, or other energy through chemical reactions that break the bonds. Food is a source of chemical energy. Our bodies store the potential energy until we need it. For example, when you sit down at the computer, your body converts some of chemical energy to another form, enabling you to move. Other common sources of chemical energy are gasoline and batteries. Mechanical Mechanical energy is associated with the movement or potential movement of an object. Springs and rubber bands have elastic potential energy; when they are stretched out they have the © Home Science Tools. All rights reserved. Reproduction for personal or classroom use only. potential to shoot across the room when released. There is also gravitational potential energy, the energy something has because of its position above the ground. For instance, when you are holding a ball, it has potential energy from the force of Earth’s gravity pulling on it. If you release it, the potential energy will be converted to kinetic energy as it falls. The closer the ball gets to the ground, the more kinetic energy and the less potential energy it has. Nuclear Nuclear energy comes from fission, the splitting of atoms, or fusion, the joining of atoms. Nuclear power plants use fission; the sun releases energy through fusion. One kind of uranium, U-235, is ‘unstable.’ When a stray neuron comes along, the unstable U-235 atom absorbs the neuron and then breaks apart into two atoms and more loose neurons. A lot of energy is released in the process. In nuclear power plants, this is used to produce power: fission is induced, which releases heat energy, which causes steam, which turns the power plant’s turbines, which powers its generators, which provides electrical power to the area. Right now a hot topic is whether we should be using more renewable energy sources than nonrenewable ones. Sources of renewable energy are ones that we use without using up them. Some examples are the sun (in sunny climates, solar panels can capture its energy), wind (we can use its energy with windmills), and water, an element and compound, which powers hydroelectric dams. Nonrenewable sources of energy, such as oil and coal, could eventually be used up; they aren’t being continually replaced the way that renewable sources are.

16 types of energy Connect the dots to complete the pictures of different examples of energy. Color the page, then draw other examples of energy that you can think of. © Home Science Tools. All rights reserved. Reproduction for personal or classroom use only.

SOLAR ENERGY STORED ENERGY

OTHER EXAMPLES OF ENERGY:

STATIC ELECTRICITY

17 different types of alternative energy Science Lesson For several decades there has been quite a bit of discussion about the damage caused to the environment by littering and pumping harmful gases into the atmosphere. Many ideas on how to protect the environment have been put into place, either by social consciousness or by law, to help clean up the earth and reduce future pollution. These ideas range from recycling, to picking up trash, to using alternative energy sources. We’re going to focus on the benefits, possibilities, and barriers that come with the use of alternative energy. Alternative energy is best defined as the use of energy sources other than traditional fossil fuels, which are considered environmentally harmful and are in short supply. Fossil fuels consist of natural gas, coal, and oil. Currently, fossil fuels are the most used energy source

to heat our homes and power our cars. To use these fuels as energy they must be burned, © Home Science Tools. All rights reserved. Reproduction for personal or classroom use only. and burning of these fuels releases harmful gases into the atmosphere, causing pollution. Another problem associated with fossil fuels is their supply: it is unclear how long oil and coal reserves will last with our current rate of consumption or if new reserves will be found before current reserves run out. Estimates on how long current reserves will last run anywhere from 20 years to 400 years. Because of these concerns with fossil fuels, more people are beginning to use alternative energy sources. Some popular alternative energy sources are wind power, hydroelectricity (water power), solar power, bio-fuels, and hydrogen. These fuels all have two things in common: their small environmental impact on the earth and their sustainability (never ending supply) as an energy source. So if alternative energy sources are supposed to fix our environmental and supply problems, why have we not switched to using alternative energy sources solely? Well, the simple answer is that alternative energy sources also tend to have common barriers to their use as widespread energy sources. These barriers include location, storage, high cost to produce and use, and inconsistent energy supply. Wind Power Wind power is not a new source of energy. For hundreds of years, human beings have used the power of the wind to send their ships across the oceans and used windmills to grind grain, pump water, and saw wood. The power of the wind can most easily be seen by using a child’s windmill. The basic concept is that when the windmill is held up in oncoming wind currents, the wind catches in the curve of the blades, causing the windmill to rotate. This is the wind’s energy at work. A wind turbine works much like an old fashioned windmill in that it also uses the wind’s kinetic energy (energy caused by motion) to turn the blades. The blades spin a shaft that is connected to a generator. A generator is a device that converts mechanical energy into electrical energy. Inside the generator, a copper coil is moved through a magnetic field by the shaft that is connected to the moving blades. This movement causes an electric current to flow through the copper coil. When the generator is mechanically powered by the wind via a wind turbine, it can make electricity. Wind power is consider a clean energy source because there are no chemical processes involved in wind power generation. No by-products are made, such as carbon dioxide, to cause air or water pollution. Wind generation is a renewable resource that will never run out, and it is a great energy source for people who live in remote areas where it may be difficult to supply them with power by use of wires connected to a power plant that is far away. The actual space taken up by a wind turbine is relatively small compared to other alternative energy sources. A diameter of only about six feet is needed at the base, making the real estate cost for a wind turbine relatively cheap. A problem with using wind power is that it is not always a guaranteed energy source. When the wind is not blowing, electricity cannot be generated, and a back up energy source must be relied upon. Wind farms are needed for commercial generation, which raises the issue of scenery obstruction caused by so many wind turbines lined up next to each other. Many people do not want to see multiple wind turbines outside their kitchen windows. Another problem is the hazard these moving blades cause for birds flying through the area. New construction of wind turbines have larger blades that rotate at slower speeds so that birds may see them and not get caught in the blades. 18 different types of alternative energy - p2 Hydroelectricity The term hydroelectricity refers to the generation of electricity through the power of water. “Hydro” comes from the Greek word hydra which means water. Like wind power, using water for power also has earlier roots than modern times. Water wheels were first used to capture water’s energy and mechanically grind grain. They were later used for pumping water, crop irrigation, driving sawmills, and powering textile mills. Today we use water turbines much like wind turbines to generate electricity. The most common source for capturing the power of water today is the hydroelectric power plant. Hydroelectric power plants usually require a dam built on a river that creates a reservoir of water. The dam holds the water back until gates open to allow the water to run through. With the help of gravity, the water runs through a pipeline, called a penstock, to the turbine. The elevation change through the penstock helps the water to build up pressure as it approaches the turbine. The moving water reaches © Home Science Tools. All rights reserved. Reproduction for personal or classroom use only. the turbine and spins the turbine’s blades. Above the turbine is a generator, which is connected to the turbine by a shaft. Like the generator in a wind turbine, the generator in a water turbine also produces electricity by moving a series of copper coils past magnets. A transformer then takes the electricity produced by the generator and converts it to a higher voltage current. The electricity is now ready to power businesses and homes via power lines. Hydroelectric power is a renewable source that causes no waste or pollution. Unlike wind power, hydroelectricity is more reliable. The energy can be stored up for use by the dam holding back water until more energy is needed. However, hydroelectricity requires a large power plant, which is very expensive to build. These power plants also require building dams on rivers, changing the ecosystem of the area. Instead of a river in the area above the dam, there is now a large lake that expands over the habitats of land animals. The amount and quality of water running out of the dam can have an adverse (negative) effect on the plants living on the land and in the water below. Solar Power Solar power is simply using the sun’s light as energy. This can be done by using a solar cell to convert the sun’s light into electricity, using solar thermal panels that use sunlight to heat air and water, or passively using the sun’s energy by letting sunlight enter through windows to heat a building. The total energy we receive from the sun each year is around 35,000 times more energy than what the human race uses, meaning this power source is probably one of the best sources for the future. The challenge lies in harnessing and storing this energy in a cost effective way. One of the most popular ways of harnessing the sun’s energy is by using photovoltaic (PV) cells, which are also known as solar cells. PV cells work by absorbing the particles of solar energy that make up sunlight. These particles are called photons. The absorbed photons are transferred to a semiconductor material, usually silicon. (Semiconductors are substances that conduct electricity more easily than insulators but not as easily as conductors like copper.) Electrons in the semiconductor are knocked loose by the incoming photons, leaving spaces in between the bonds of the atoms. Both the loose electrons and the open spaces can carry an electrical current. PV cells are built with one or more electric fields to control the flow of the electrons, thus controlling the flow of the current. When metal contacts are placed on the top and the bottom of a PV cell (much like a battery), we can extract this electrical current to use it in our everyday lives. Like the above alternative energy sources, solar power is renewable and nonpolluting. Unlike wind turbines and hydroelectricity, photovoltaic conversion to electricity is direct, meaning an expensive, bulky generator is not required. Like wind turbines, solar power can also be used in remote locations where it would be economically impossible to provide power from a far away power plant. Solar power can also be very efficient in providing heat and light through the use of solar ovens, solar water heaters, solar home heaters, and the use of skylights. Solar power shares a common drawback with wind turbines: their unpredictability. Solar power only works when the sun is out, making a PV cell ineffectual at night and hit or miss during a cloudy day. For these times, power storage needs to be implemented in order to make solar power the main power source. 19 different types of alternative energy - p3 Many forms of solar power are still not economically practical. Photovoltaic power stations are expensive to build and are only about 10% efficient in producing energy. It takes about five years for a power station to produce the same amount of energy that went in to the initial building of the power station. With current technology, solar power is best used on a smaller scale, such as individual homes. Bio-fuels There are many energy sources that fall under the category of bio-fuels: biomass, bio-diesel, ethanol, and methanol are just a few. The basic idea here is to use organic matter (usually plant derived) as a fuel source. Biomass refers to using garbage and vegetation as a fuel source. When garbage is decomposing (breaks down) it produces a gas called methane that can be captured and

later burned to produce energy that can be turned into electricity. Vegetation can be burned directly, © Home Science Tools. All rights reserved. Reproduction for personal or classroom use only. much like fossil fuels, to generate energy. While these methods do help in the cost and sustainability areas, they still cause a significant environmental impact much like fossil fuels. Ethanol and methanol are two alcohols that are made from biomass. Ethanol is usually made from corn, but can also be made from agricultural, logging, and paper wastes. Methanol is also known as wood alcohol because it can be made from wood; however, most methanol is produced using natural gas because it is cheaper. Whereas bio-diesel is the alternative for diesel engines, ethanol and methanol are the alternatives for gasoline engines. Most private vehicles have gasoline engines and can use ethanol blends with little or no modification of the engine. Ethanol also burns cleaner and produces lower greenhouse emissions than gasoline. However, comparing the price of ethanol with the price of gasoline is a bit tricky. One gallon of pure ethanol contains 34% less energy than one gallon of pure gasoline. A common ethanol blend, E85, is a mixture of 85% ethanol and 15% gasoline and produces 27% less fuel economy than 100% gasoline. So in order for E85 to cost less than gasoline, it must have more than a 27% price reduction than gasoline. Gasoline that costs $3.00 a gallon has the same fuel economy as E85 that costs $2.19 a gallon. Bio-diesel is made by combining a vegetable oil, such as canola or soy oil, and an alcohol such as methanol or ethanol. A catalyst is often added to increase the rate of the reaction between the vegetable oil and alcohol. This process to make bio-diesel is called transesterification (for more information on transesterification, click here). This chemical process causes the glycerin to separate from the fat in the vegetable oil, leaving behind two products: methyl ester or ethyl ester (the chemical name for bio-diesel) and glycerin. Glycerin is a valuable byproduct often used to make soaps and other products. Bio-diesel is considered an ideal fuel because it is clean burning and can be used in any diesel engine. It is often mixed with regular petroleum diesel to avoid complications with cold weather usage. Pure bio-diesel gels at a higher temperature than petroleum diesel. (Soy bio-diesel bought in the U.S. begins to gel up at about 40 °F.) This means that it is harder to start a truck in sub-zero temperatures that runs on bio-diesel than a truck that runs on petroleum diesel. Bio-diesel costs more to produce and therefore costs more to buy than petroleum diesel. Otherwise, bio-diesel tends to work as well as petroleum diesel. Pure bio-diesel and bio-diesel blends release fewer greenhouse gases, are biodegradable (able to decompose by natural processes), and can extend the life of diesel engines. Some filling stations that provide diesel also provide bio-diesel.These retailers are more prevalent in the Midwestern states. Here is a map of retailers who sell bio-diesel in the United States.

20 different types of alternative energy - p4

Hydrogen One of the most promising alternative fuels of the future is hydrogen. Its large supply and clean burning properties have many scientists and environmentally conscious citizens looking to it as the solution to replacing fossil fuels without drastically changing our current lifestyles and dependency on personal vehicles. Unlike fossil fuels, it is a non-carbon fuel so when it is burned it does not produce more carbon dioxide. Hydrogen is the simplest and most abundant element found on earth and is found in water, air, and all organic matter. However, even with these all these positives, two major problems stand in the way of using hydrogen as a main fuel source: its production and its storage.

There are two main ways to produce hydrogen: electrolysis and reforming natural gas. Electrolysis © Home Science Tools. All rights reserved. Reproduction for personal or classroom use only. involves using an electric current to split the water molecule into hydrogen and oxygen. (To separate hydrogen at home using electrolysis, click here.) In the process of reforming natural gas, methane (which is a principal component in the natural gas used to produce hydrogen) is heated using steam, causing a reaction between the methane and water vapor that produces hydrogen, carbon dioxide, and trace amounts of carbon monoxide. Currently, both methods use natural gas to produce hydrogen. Reforming methane requires splitting the hydrogen from the carbon in methane, but electrolysis requires a power source to produce electricity to split the water molecule. Natural gas is most often used as the fuel source to produce this electricity. Since both of these methods require the consumption of natural gas to produce hydrogen, hydrogen costs more to use than natural gas. Hydrogen can be used to power vehicles in two ways: to produce electricity in a fuel cell or be used directly in an internal combustion engine. Using hydrogen in a fuel cell is the cleaner method. A fuel cell is an electrochemical device that combines hydrogen and oxygen to produce electricity. Its only by-products are heat and water, which do not pollute the environment. When using hydrogen directly in an internal combustion engine, the hydrogen is burned with the outside air (which is about two-thirds nitrogen) producing nitrogen based oxide gases, which cause some pollution, and water vapor. Whether hydrogen is used directly in an internal combustion engine or in a fuel cell, both methods require the storage of hydrogen for use as the vehicle is driven. On a weight basis, hydrogen produces the most energy when burned compared to any other fuel — one pound of hydrogen produces 2.6 times more energy than one pound of gasoline. However, hydrogen is a gas so one pound of hydrogen takes up four times the amount of space as does one pound of gasoline. For example, a vehicle that holds 15 gallons of gasoline would need to hold 60 gallons equivalent value of hydrogen to produce the same amount of energy. The tank in the vehicle would have to be the size of two average bathtubs to hold the hydrogen needed in order to drive a reasonable distance without refueling. However, the 15 gallons of gasoline would weigh 90 pounds whereas the 60 gallons of hydrogen would only weigh 34 pounds. To solve this space problem, hydrogen can be turned into a liquid which takes up less space than hydrogen as a gas, but in order to turn hydrogen into a liquid, it must be cooled and kept to -423.2 ° Fahrenheit. Storing hydrogen as a gas or a liquid is very expensive and cumbersome. Still, there is hope on the horizon. The United States Department of Energy has offered grants to scientists to find ways to improve the storage of hydrogen on small vehicles by improving compression and liquefaction of hydrogen, using metal hydrides to store more hydrogen without adding too much weight to the vehicle, and improving the use of adsorbent materials to collect and hold hydrogen gas on the surface of a solid. However, even if we overcome the storage problem, we still face the hurdle and expense of replacing all gasoline-powered cars with hydrogen-powered cars and replacing gasoline-filling stations with hydrogen-filling stations to become a hydrogen-basedAmerica.

21 make your own solar car

WHAt YOu NEED: for the car body:  2 solar cells  Cardboard milk carton  2-4 alligator clip leads  Water bottle  Rubber bands   Cardboard Small electric motor  Foam board (Look at hobby or electronics stores, or similar materials and make sure you get one with a motor pulley)

for the axles: for the wheels: © Home Science Tools. All rights reserved. Reproduction for personal or classroom use only.  Stiff wire or wooden  Plastic bottle caps, shish-kabob skewers  Film canister caps,  Straws or eye screws  Toy wheels to mount the axles such as K’nex, etc.

In this project you will need creativity and experimentation to design and build a car powered by two solar cells and a small electric motor. The National Renewable Energy Laboratory has a PDF curriculum that will also give you ideas and help you learn about the scientific and engineering principles behind building a solar car. (Adult supervision is recommended for this project.) WHAT YOU DO: 1. Choose a material for the car body, which is called the chassis. Think carefully about this: you want something strong, but also something lightweight so it needs less power for the motor to move it. (But be careful — if it’s too light, it can easily get blown about by the wind.) A big part of engineering is finding the right balance between weight and strength. 2. Use a nail to poke a small hole in the center of your wheels. Make sure the stiff wire or wooden skewers you use for axles fit in the holes tightly. Take an extra cap and cut off the sides, leaving just the top part, which usually has a small inner rim to help keep the bottle from leaking. Glue this cap to one of your wheels. You have just created a pulley for your driving wheel; the inner rim of the extra bottle cap will support your car’s drive belt. (You can try using a film canister cap for this step instead of cutting a bottle cap. If you are using toy wheels like K’nex, you can just use a smaller wheel mounted on the inside of your main wheel to act as the pulley.) 3. Now, mount your axles onto the chassis. Depending on what your chassis is made of, you can thread the axle through eye screws mounted on the bottom. Another easy method is to tape straws on the underside of the chassis and thread the axles through them. (Use our balloon rocket car project as reference for how to do this.) 4. Attach the small motor pulley to the motor shaft. Determine where to mount the motor by connecting the driving pulley with the motor pulley using an elastic band as a drive belt. Position the motor so the band is slightly stretched (but don’t stretch it too much!) Mount the motor with glue or tape it in between a small frame of wood or cardboard blocks.

22 make your own solar car - page 2

5. Choose a material for the car body, which is called the chassis. Think carefully about this: you want something strong, but also something lightweight so it needs less power for the motor to move it. (But be careful — if it’s too light, it can easily get blown about by the wind.) A big part of engineering is finding the right balance between weight and strength. 6. Use a nail to poke a small hole in the center of your wheels. Make sure the stiff wire or wooden skewers you use for axles fit in the holes tightly. Take an extra cap and cut off the sides, leaving just the top part, which usually has a small inner rim to help keep the bottle from leaking. Glue this cap to one of your wheels. You have

just created a pulley for your driving wheel; the inner rim of the extra bottle cap © Home Science Tools. All rights reserved. Reproduction for personal or classroom use only. will support your car’s drive belt. (You can try using a film canister cap for this step instead of cutting a bottle cap. If you are using toy wheels like K’nex, you can just use a smaller wheel mounted on the inside of your main wheel to act as the pulley.) 7. Now, mount your axles onto the chassis. Depending on what your chassis is made of, you can thread the axle through eye screws mounted on the bottom. Another easy method is to tape straws on the underside of the chassis and thread the axles through them. (Use our balloon rocket car project as reference for how to do this.) 8. Attach the small motor pulley to the motor shaft. Determine where to mount the motor by connecting the driving pulley with the motor pulley using an elastic band as a drive belt. Position the motor so the band is slightly stretched (but don’t stretch it too much!). Mount the motor with glue or tape it in between a small frame of wood or cardboard blocks. 9. Use clear plastic tape to attach the two solar cells together side-by-side; then connect them in a series circuit using the alligator clip leads. Connect the positive terminal of one cell to the negative terminal of the other. Connect the remaining terminals to the motor. If the motor spins the wrong way, switch the leads where they connect to the motor. Once it’s connected properly, you’ll probably want to use to tape to help keep the wires under control. 10. Mount the solar cells on the chassis at an angle where they will receive the most sun. Take your car outside to a sunny sidewalk, connect the drive belt, and watch it go! 11. Designing and building a car from scratch involves a lot of perseverance and trial and error, so don’t be discouraged if yours doesn’t work perfectly right away. Experiment to see if you can improve the design of your solar car. How fast does it go? Does it drive straight? How would it perform with only one solar cell? What if you used smoother wheels for less friction? Keep testing new ideas to make your car work better.

23 build a mousetrap car

WHAt YOu NEED:  Wooden snap-back mousetrap  Foam board (usually found at  Duct tape a craft store)  4 eye hooks  String  Wooden dowel that fits inside  Ruler or straight edge the eye hooks  Utility knife  Heavy cardboard  Pliers  Large and small rubber bands © Home Science Tools. All rights reserved. Reproduction for personal or classroom use only. Are mousetraps good for anything more than catching mice? safety note Actually, yes. Mousetraps can be used to power a car! This project results in a simple mousetrap car. It probably won’t go Mousetraps are very far or fast, but you can see how stored, potential energy dangerous! If one snaps is converted into kinetic energy. back on your hand it WHAT YOU DO: could break a finger. This project requires 1. Cut four wheels out of a piece of foam board or corrugated adult permission and cardboard (adult supervision is necessary). Make the back supervision. wheels about double the diameter of the front wheels. (Use a compass to draw the circles, or trace around a bowl or cup.) 2. Give your wheels some traction by stretching large rubber bands around each wheel. For the small wheels, you could also try using a section of a balloon. Remove any metal or plastic teeth on the mousetrap with pliers. Remove the rod that is used to set the trap. 3. Cut a piece of strong cardboard so that it is slightly larger (about 1/2″) than the mousetrap on every side. This is the base of the car, known as the chassis. Attach the mousetrap to the chassis, using duct tape. Don’t cover up the spring in the middle of the trap or the “snapper arm.” 4. Screw the eye hooks onto the bottom of the cardboard chassis, one in each corner. Use a ruler to make sure that the eye hooks are aligned with each other. Cut the wooden dowel so you have two pieces that are both about two inches longer than the width of the chassis. These will serve as your axles that rotate the wheels. Stick the dowels through the eye loops. Make sure that the axles are straight and that there is room for them to spin in the eye hooks. 5. Cut holes a little bit smaller than the dowel through the center of each wheel, then attach the wheels to the chassis. Put the large wheels on the back of the car, opposite the snapper arm. 6. Wrap a small rubber band around the axle on either side of each wheel so the wheels can’t fall off. Tie a string very tightly to the snapper arm on the mouse trap. The string should be long enough to just reach to the back axle. Pull back the snapper arm until it reaches the other end of the trap, carefully. (You may need help.) Hold the snapper arm in place and wrap the string tightly around one side of the axle. Holding the string tightly, set the car on the ground and carefully let go of the trap – the string should be wound tight enough that it holds the trap in place. Let go of the string (after making sure all hands are out of the way!). The trap will snap forward, propelling your car.

24 build a mousetrap car - page 2 what happened: A set mousetrap is full of potential energy which, when released, is converted to kinetic (motion) energy. The design of your car allowed that energy to be transferred to the axle to make the wheels turn. When the trap snapped closed, it yanked the string forward. As the string was pulled, friction between it and the axle caused the axle to rotate, spinning the wheels and moving the car forward. There are many different ways to build a mousetrap car. Your simple model moves forward a few feet, but how could you design it to go longer distances? Or how could you design it to go faster? Here are some things to think about: © Home Science Tools. All rights reserved. Reproduction for personal or classroom use only. Wheel-to-axle ratio For distance cars, larger wheels are best. Every time your axle turns one time, so do your wheels — if the wheels have a much larger diameter than the axle, the car will go further on each turn of the axle than it would if the wheels were smaller. It takes more force to accelerate a car with a large wheel-to-axle ratio, so smaller wheels will work better if you want your car to be fast. Inertia Newton’s first law of motion states that objects at rest tend to stay at rest, and objects in motion tend to stay in motion unless acted on by an external force. Inertia is the tendency to resist changes in motion, and the more inertia something has, the more force will be necessary to change its state of motion. If your mousetrap car is very heavy, it will require greater force to get it moving. To avoid too much inertia, think about how you can build a lighter car. The rate of energy release If the energy from the mousetrap is released quickly, your car will accelerate quickly and run faster. However, it will also run out of energy sooner. If the energy from the mousetrap is released slowly, the car will move slower, but be powered for a longer distance. One way to try making the energy release slower is to lengthen the lever arm by attaching something (pencil, dowel, etc.) to the snapper arm and tying the string to the end of that. (This will give you a longer piece of string than the one tied directly to the snapper arm.) Friction Analyze all the points of friction on your car, where two substances rubbing together can slow the car down or bring it to a stop. Think especially of how to reduce friction between your axle and the eye hooks attaching them to the body of the car. Some friction is good, however – the friction that enables the wheels to grip the floor is called traction, and without it, the force of the trap may make your wheels “spin out” instead of propelling the car forward. The above procedure used rubber bands to provide traction; can you think of a better way? Other ideas for improving the car: • Make it more durable by using lightweight wood such as balsa or basswood instead of cardboard. • Use CDs or records as the wheels. • Glue a small hook to the axle and connect the string to it with a small loop, then wrap the string by turning the wheels in reverse.

25 honey bee memory

WHAt YOu NEED:  5 index cards  1/4 cup sugar  5 small dishes  A black marker  5 ziplock bags  3/4 cup water

Have you ever wondered how bees and butterflies know where to find good feeding

spots? These insects don’t have sharp vision, but they see polarized light (which © Home Science Tools. All rights reserved. Reproduction for personal or classroom use only. tells them direction based on where the sun is) and patterns of ultraviolet light on bright-colored flowers with lots of nectar. Bees also recognize man-made patterns; sometimes beekeepers put a symbol on a new hive so their bees can remember which is the right one.

Do this experiment to test how well bees recognize patterns – and see if you can fool them! You’ll need about a week to do this project, with time to check your homemade bee feeder every day. WHAT YOU DO: 1. On each of the index cards, draw a simple shape with the marker. (You might draw a star, circle, cross, triangle, and square.) Make the shape big enough to cover most of the card and fill in the shape so that it’s solid black. When you’re done, stick each card inside a ziplock. This will protect it from being ruined outside.

2. Set the bags outside in a flat, sunny spot where they won’t be disturbed. Make sure the shapes are facing up. Each one should be placed a couple feet away from the others. If you live in a windy area, use rocks or a stake to hold down the bags!

3. Mix up some sugar water, the “nectar” that will attract bees and other insects. (Real nectar, from flowers, is a similar sugary liquid.) Heat the water until it’s about to boil (the easiest way is to microwave it for 60-90 seconds). Then stir in the sugar until it’s dissolved. Pour the sugar water into one of the small dishes; fill the other four with plain water. Set a dish outside by each of the ziplocks. Make sure you remember which dish has the sugar water!

4. During the next few days, keep track of what kinds of insects visit the dishes. How many days does it take before bees find the one with sugar water? A few days after you’ve seen bees at the sugar water dish, switch cards so that the shape that was next to the sugar water is now by a dish of plain water. What happens in the next two days? Do the bees come right to the sugar water, or do they land on the dish with the card that used to be next to the sugar water? Now leave the cards where they are, but switch the sugar water dish with another dish of plain water. How do the bees respond?

26 smelling bee activity

WHAt YOu NEED:  A variety of foods with various types  Cotton balls of scents. A few easily recognizable  Handkerchief or other blindfold options include: pickles, mustard,  Film canisters or other small, peanut butter, coffee beans, mint opaque containers with lids, like empty single-serve yogurt candy, banana, and vinegar. containers.

Despite having compound eyes, bees and ants don’t use their eyes the same way © Home Science Tools. All rights reserved. Reproduction for personal or classroom use only. we do; in fact, some ants are blind! So instead of their sight, bees and ants often will rely on their sense of smell. Special scents called pheromones help them recognize each other and their homes. In this game, you’ll be the bee (or ant) and see if you can tell different scents apart. variation 1: Put a cotton ball soaked in the food (or a small portion of the food) in each container. Have the blindfolded children smell the container and see if they can guess the scent.

Variation 2: If playing the game with several children, divide each scent-soaked cotton ball into two containers. Pass them out to the children and have them take turns sniffing each others’ containers and try to find their “pheromone friend,” the person with the matching scent.

Variation 3: Make a smelling scavenger hunt. Hide a honey pot or honey bear and tell the children they must sniff their way back to the beehive. Make a trail of scent-filled containers that leads to the “hive.” Devise a “path” they must sniff out to in order to find their way back to the “hive.” Give the children directions to the hive using different scents to mark the trail. (Use pictures for younger children.)

27 ladybug life cycle What to do: 1. Color the ladybug life cycle pictures below. 2. Cut out the pictures on the dotted lines. 3. Glue them to the white rectangles on the Ladybug Life Cycle chart on the next page to show the correct order of a ladybug’s life cycle. 4. Write the name of each stage in the correct spots (these are the names of the stages: adult, larva, egg, pupa). © Home Science Tools. All rights reserved. Reproduction for personal or classroom use only.

STAGE 1: ______

STAGE 4: STAGE 2: ______

STAGE 3: ______

29 make a butterfly feeder - jar method

WHAt YOu NEED:  Small jar (like a baby food jar)  Sugar  Hammer and nail  Water  Kitchen sponge  Construction paper  String or artificial flowers

Construct a butterfly feeder using a baby food jar and some sugar water. Adult © Home Science Tools. All rights reserved. Reproduction for personal or classroom use only. supervision is recommended. WHAT YOU DO: 1. Make some butterfly food with nine parts water and one part sugar (use tablespoons or teaspoons depending on the size of your jar). Add the sugar to the water and boil in a pan until it is dissolved. Let it cool while you prepare the butterfly feeder.

2. Have an adult help you use a nail and a hammer to punch a small hole in the lid of the jar.

3. Cut a strip of the kitchen sponge and pull it through the hole in the lid, leaving about a half-inch sticking out from the top of the lid. You want the sponge to be a tight fit – it should get soaked with the sugar water, but not drip. (Test it by putting water in the jar and turning it upside down. If it leaks, try a bigger piece of sponge.)

4. Next, make a hanger. Tie some string around the mouth of the jar. Cut two more lengths of string about 30′ long. Take one and tie an end to the string around the mouth of the jar. Attach the other end on the opposite side of the jar to make a loop. Tie the second length of the string in the same way to make a second loop perpendicular to the first one. Use one more piece of string to tie the tops of the loops together. Now turn the jar upside down and make sure it hangs steadily.

5. Decorate the jar with brightly colored construction paper (flower shapes are best) or artificial flowers. The ‘prettier’ it is, the more it will attract butterflies!

6. Fill the jar with the cooled sugar water, screw the lid on tightly, and turn the jar upside down.

7. Hang your feeder outside and wait for the butterflies to come! 30 pond study Summer is a great time to learn about and observe the tiny creatures that live in lakes, ponds, or puddles. To collect some specimens, scoop a cup or so of pond water into a jar. Take your sample near plants, as the most specimens will be located there. Preferably, you should observe the sample within 24 hours, as the composition of it will change over time. Also, make sure the specimens have air! 1. While you are at the pond, you might want to take advantage of the opportunity for a more complete life science study. You can look for animal tracks, identify plants, and look at the insect population. Look carefully at the soft ground around the water for animal tracks. You might find bird or mammal tracks, which can be identified with a guide book. For bird tracks, you might want to have your kids draw what the prints look like. With the larger animal tracks, you can use plaster of paris and a tin can with both ends cut out to © Home Science Tools. All rights reserved. Reproduction for personal or classroom use only. make a cast of the prints. Carefully remove any debris from a track, then firmly press the can into the soil around it. Mix 1/4 to 1/2 a cup of plaster with enough water to make it the consistency of pancake batter. Pour the mixture over the print, until there’s a layer of one inch in the bottom of the can. You’ll need to let the plaster of paris dry for about an hour before you can remove the can, and then for 24 hours until you can remove the cast from the can. 2. Use a guide book to identify the plants and flowers around the pond. How do the plants around the water differ from those further back, or from the aquatic plants in the water? What shape are the leaves? Be sure to look for interesting features such as berries, seeds, or thorns. Your children might enjoy sketching some of the plants they’ve identified. 3. There’s usually an abundance of insect life around water. Look at the water first; are there insects on the surface, or hovering around it? How do they move? Do you see different insects further away? (Look under rocks or pieces or wood along the shore.) What about on plants? Use a guide book to identify as many insects as you can. Have your kids sketch some of the different specimens they see; or, if they want to, have them catch insects to be preserved in a collection. You might also find snails, minnows, frogs, snakes, and turtles. 4. You can observe your pond water sample with either a microscope or a magnifying glass, although some organisms will be visible without magnification (daphnia, hydra, and planaria, for example). Use a dropper to ‘catch’ visible specimens. Most organisms can be viewed without high magnification, but if you want to use a compound microscope, place a drop or two of the water on a clean slide (concave slides work best). You might want to add a drop of methyl cellulose solution to quiet the protozoa in the water, so that you can observe them more easily. Set a coverslip over the section of the slide where you placed the water sample. If you’re using a magnifying glass or a stereo microscope, pour a little of the pond water into a petri dish or other clear, shallow dish and then use the dropper to add specimens. 5. Use a dichotomous key to identify protozoa and algae, or else a pond identification guide. When trying to identify a specimen, look at specific features: what shape is it? Does it have cilia (tiny hair-like structures) to help it swim? What color is it? Have your children jot these observations down as well. 6. If you don’t have any pond water available, use our Protozoa Hatchery Kit to grow the sort of specimens you’d find in a pond. 31 make an insect collection

WHAt YOu NEED:  Insect net  Forceps  Relaxing  Killing jar  Pinning block chamber supplies  Ethyl acetate  Spreading board (plastic lidded box,  Observation jar  Insect pins paper towels)  Insect field guide  Display case

From an itty-bitty bed bug to a massive atlas moth, the world of insects is crawling (and flying!) with different specimens to discover. Making an insect collection is one of the best © Home Science Tools. All rights reserved. Reproduction for personal or classroom use only. ways to learn about insects, as you’ll observe them up-close. Finding and Catching Insects: Spring or summer is a wonderful time to start making an insect collection! By late summer many insects have gone through their stages of metamorphosis and emerged as adults. Even though insects all have six legs and three main body parts (head, thorax, and abdomen), the variety of shapes, colors, and sizes is astonishing. Insects include butterflies, moths, grasshoppers, praying mantises, beetles, dragonflies, and bees, plus many more. Insects are abundant in many different habitats. Try looking for them… …around water. Look for dragonflies in the air, water striders on the surface, and different kinds of water beetles on plants growing in the water. Use a fish net and/or a turkey baster to collect insects out of the water. Also look around mud puddles – lots of insects, including butterflies, will drink from them to gain necessary minerals. …in the ground. Dig at the base of trees or plants where you have seen caterpillars before—you may find the pupae of moths in cocoons. Lift up stones or boards to find beetles or non-insects like sow bugs, spiders, and centipedes. …on plants. Flowers attract lots of different insects, including bees and butterflies. Plants also provide homes to ladybugs, caterpillars, leafhoppers, and many more. Look for leaves that have been eaten; there’s a good chance you’ll be able to find the insect who did the damage. Also check for beetles underneath loose bark on trees or around stumps. (Woodpiles are a great place to find hidden insects, too.) …near lights. At night insects will often congregate around streetlights or porch lights. using an insect net: When searching for insects outside, look on flowers, in gardens, on decaying leaves, and through the air. If looking for insects in a field, use the sweep method: Carefully swing your net through the top edge of the grass and see what you catch in the end of your net.

When attempting to catch an individual bug with a net, move slowly until you are in range. Position the net under the insect, then swing your net upward and quickly turn the handle so that the net flops over its ring and the captured insect cannot escape. If you bring the net over the insect and down to the ground, raise the end of it so that the insect can fly to the closed top, then stick a container (a killing jar, if you intend to preserve the insect in a collection) under the net and carefully move your insect down into it. Consider the complete Deluxe Insect Collecting Kit, which contains all items necessary to make an insect collection from the insects you catch. 32 make an insect collection - page 2

To keep a butterfly from beating its wings against the sides of a container and damaging them, you can “stun” it by pinching the thorax (the middle part of the body) with your thumbnail. This may take some practice to get right, but once you’re able to do it well you can carry stunned butterflies safely in glassine envelopes with their wings folded together. Observing and Identifying Insects: There are about a million insect species of all different colors, shapes, and sizes! However, despite the many differences, all insects share a few basic characteristics:

Exoskeleton – Rather than bones inside their bodies, insects have a hard protective covering on the outside. © Home Science Tools. All rights reserved. Reproduction for personal or classroom use only. Antennae– Insects usually have one pair of antennae on their head used for touching and smelling. Three body divisions – Insect bodies are divided into the head (with its eyes, mouth, and antennae), the thorax (where its legs and wings are), and the abdomen. Six legs – All insects have six legs attached to their thorax.

You’ll likely find “bugs” that don’t have all these characteristics—like spiders and ticks, which have eight legs, and millipedes, which have many, many more. It’s up to you whether or not to include these bugs in your insect collection.

When observing a live insect specimen that you intend to release later, carefully put it in the Deluxe Bug Magnifier. Is its body soft or armor-covered? What are its antennae like and how does it use them? Based on its mouth, can you tell its eating habits? Does the specimen walk jerkily or quickly? If it has wings, what does its flight look like? Use these features to help you identify the insect, using a high-quality guide book. Using a Killing Jar: First, charge the jar by adding a capful of ethyl acetate to the plaster cartridge in the bottom. Then put your insect in and quickly close the lid. After a few minutes, the insect should be dead, but you may wait a half hour before removal to be sure. Insects left in the jar for a day or more may become too soggy and wet to use. Use forceps, if you have them, to carefully take a specimen out of the killing jar. Either pin the insect immediately (see steps below) or store it in a glassine envelope until you are ready for the next step.

You may dispatch several small insects in the jar at once. But kill larger insects and butterflies separately so they don’t damage each other.

If you do not have a killing jar right now, or have caught many insects at one time, you can also try freezing one for several days in a small airtight plastic container, which works best for small crawling insects. This method takes longer, and is unreliable for large insects and butterflies.

33 make an insect collection - page 3

Using a spreading board: To make sure your insects dry in the right position for display, use a spreading board and insect pins. (You can make your own spreading board with strips of cardboard.) For large winged insects like butterflies, carefully insert a pin through the right side of the thorax by gently pinching the thorax to spread the wings enough to pin it. Place the insect’s body in the groove on the board – it varies in width for different-sized insects. Gently press the wings down so they lie spread out flat, then put a thin strip of paper over each wing and pin the ends of the strip to the board. The drying process may take up to two weeks for your insect. Once the specimen has dried, remove the paper strips, but don’t try to remove the pin through the thorax! Use that pin to mount it in a display case. © Home Science Tools. All rights reserved. Reproduction for personal or classroom use only. Identifying and Labeling Insects: Since insects can be beautiful or strange or scary-looking, it’s fun to make a collection just for display. But if you’re making a collection for school or researching which insects live in your area, you’ll want to take the extra step to identify the specimens you collect. Take notes of where you found each insect (such as what plant it was on) while you’re out collecting, and then use an identification guide when you get home to find the scientific and common names. Write or print out a small tag (card stock or other thin cardboard works well) with the name, and attach it to the pin that you use to hold down your insect. You may also want to list the date and place where you found the insect. Notes:

34 solar energy matching game

Match the pictures to see how solar energy can be used instead of other types of energy. What to do: 1. Cut out each square 2. Turn all of the squares over so you can’t see the pictures. 3. Flip two squares over at a time, to try and make a match! (example: the light bulb and sunny window © Home Science Tools. All rights reserved. Reproduction for personal or classroom use only. are a match, because they both give light)

35 solar system coloring page What to do: 1. Color each planet it’s true colors. You can identify each based on size and physical features. 2. Number the planets 1-8 in order from closest to farthest from the sun. 3. Cut out the planets and make a model of the solar system. © Home Science Tools. All rights reserved. Reproduction for personal or classroom use only.

36 star chart How to use this star chart: 1. Go outside after dark and stand facing south. Hold the chart up over your head so that the N points behind you towards north. 2. Look for the Big Dipper. Once you find it, look down and to the left to find the bright star Polaris. How many of the stars and constellations can you find? Note: These are just some of the constellations and stars you might be able to see in the sky. The constellations change positions throughout the night, so you’ll be able to see some early in the night and others later. You can also use the star chart in a dark room. Ask an adult to help you use a straight pin to poke holes through all of the white dots then have someone hold a flashlight in a dark room for you while you hold up the chart and look at the “stars.” © Home Science Tools. All rights reserved. Reproduction for personal or classroom use only.

37 summer stargazing There are few things more glorious than viewing the night sky on a clear day, away from the lights of cities. Summer is the perfect time to go stargazing! With this short guide you will learn what to look for this summer as well as get a few general astronomy tips. Finding the North Star Constellations are groups of stars that form patterns in the sky that look like animals or people. Many of these patterns have been named after figures in Greek mythology. Finding two main constellations will lead you to Polaris (also called the North Star, because it is aligned with the magnetic north pole), which serves as a compass in the night sky, showing you which way north is year round.

Ursa Major: the Big Dipper © Home Science Tools. All rights reserved. Reproduction for personal or classroom use only. If you have a star locator, it can help direct you, but you can find Polaris without one as well. Look for four stars that make a square, or box, with an arc of three bright stars coming out of one corner. You just found the Big Dipper, part of the constellation named Ursa Major (Latin for Big Bear). At the side of the dipper opposite of the handle, there are two bright stars. Follow the line these stars make to Polaris, a star of about the same magnitude, or brightness. Polaris is on the end of the handle of the Little Dipper (part of the constellation Ursa Minor, or Little Bear). Now that you know which direction is north, it will be easier to navigate the night sky. Planets The brightest planets can be seen easily with the naked eye; Venus and Jupiter are the easiest to spot in the summer. If you’re not sure whether it’s a planet or a star, there is a simple way to find out. Fix your gaze on one point of light. If it seems to glimmer or flash, it is a star. Planets will shine with a more steady, even glow than stars do. Another way to tell is by monitoring the sky for several nights in a row. Stars will appear to circulate, but stay the same distance apart from each other, whereas planets appear to move independently, with no fixed relation to the stars or other planets. Meteor Showers If you would like to watch part of a meteor shower this summer, the best dates are in mid-August. Every year in late summer, a meteor shower appears close to the constellation Perseus. These impressive meteors, called the Perseids, can appear at a rate of 120 per hour (that means two meteors every minute). The less moonlight there is, the better it is to see the meteors, or “shooting stars.” If you can, try to view the meteors early in the morning, while it is dark. Look for the Perseids in the northeast part of the sky. To watch a meteor shower, be prepared to spend a few hours sitting outside! Meteor showers can be seen as soon as it gets dark, but optimal viewing begins about 11pm. You will want to go some place far away from large cities, because light pollution makes it impossible to see the night sky clearly. Give your eyes 20 minutes to adjust to the dark before gazing towards the corner of the sky where the meteor shower is expected to appear. You may want to use binoculars, but they are not necessary. While you’re outdoors, you may also want to look for constellations, stars, or planets using a star locator or guide book. 38 summer stargazing - page 2

The Summer Triangle If you have a telescope, find the Summer Triangle, which can help you locate other night sky sights. The two stars by the handle of the Big Dipper will lead you to the Summer Triangle. Trace a line through the stars until you reach a very bright star, Vega. The star locator can also help you locate Vega, one of the brightest stars in the summer sky. To the left is another bright star, Deneb. Look below both stars and you will find another bright star, Altair, the final star in the Summer Triangle.

Each of the stars in this triangle is part of a constellation. On a clear night you can

make out Vega’s small constellation, Lyra (or the Harp) which is shaped like a box with © Home Science Tools. All rights reserved. Reproduction for personal or classroom use only. one bright star (Vega) coming out of one corner. Deneb makes up the tail of its constellation resembling a bird in flight, Cygnus (the Swan). Altair makes up the head of its constellation Aquila (the Eagle, also sometimes called the Vulture). Other Stars and Constellations Use the Summer Triangle to guide your eye towards other exciting sights in the night sky! Some of these are best viewed with the powerful magnification of a telescope.

The Ring Nebula (M57) is a colorful circle of gas formed when the outer layer of a star expanded into space after it had run out of gaseous fuel to burn. To find the Ring Neb- ula, look in the area between the two stars furthest away from Vega in the Harp constellation. The doughnut-like shape of M57 can be seen with even a small telescope, but the more powerful the telescope is, the more detail of color and shape you will be able to see.

Another astronomical object to view with a telescope is the double star Albireo, which is at the head of the Swan constellation. What may at first appear to be a single star is actually two faraway stars; one is blue, and the larger, brighter star is yellow. This amazing contrast can be viewed with low magnification on almost any telescope. Don’t forget to examine the moon and the planets while you are using a telescope this summer! Notes:

39 phases of the moon Astronomy Science Project

WHAt YOu NEED:  An orange (or a Styrofoam ball of a  A room that can easily be size similar to an orange) made dark  A desk lamp (or any lamp with a  An adult’s help removable shade)  A pencil

WHAT YOU DO: © Home Science Tools. All rights reserved. Reproduction for personal or classroom use only. 1. Get an adult to help you push the sharp end of a pencil halfway through the orange; push it far enough to keep it stable when you hold the unsharpened end.

2. Find a room that you can make dark by turning off the lights and closing shades. If you can’t make it dark enough, do the experiment when it is dark outside or use blankets to cover windows.

3. Set the lamp on a table or dresser so it is about the same level as your head when you’re standing. Turn the lamp on and remove the shade or turn the lamp so that the bulb is facing toward you (if you’re using a desk lamp).

4. Stand about 3 feet in front of the lamp and hold the pencil with the orange attached to it out at arm’s length. The orange should be between you and the lamp. For this activity, you represent Earth, the lamp is the sun, and the orange is the moon.

5. To see the moon’s phases, slowly turn your whole body to the left, keeping your arm straight out in front of you with the orange at eye level. This is how the moon orbits the Earth. Keep turning in the same direction until you have gone in a full circle and are facing the lamp again. Keep your eyes on the orange and watch the shadows on it very carefully to see the phases of the moon as we see them from Earth.

WHAT HAPPENED: It takes around 29 days for the moon to orbit the Earth once and the same amount of time for the moon to spin around one complete time on its axis. That means that we always see the same side of the Moon! However, we do see the moon changing as it goes through its phases. 40 New Moon While facing the lamp (sun), the surface of the orange (moon) facing you (Earth) was dark, even though the other half of the orange, facing toward the lamp was bright. This is the first phase of the moon, called new moon. We can’t see the moon at all during this phase!

Waxing Crescent As you began to turn away from the lamp, a shadow still covered most of the orange, but you probably saw a small crescent shape of light on the right side of the orange. This phase is called waxing crescent.

First Quarter The next phase is called the first quarter: the light (sun) shone on the half of the orange © Home Science Tools. All rights reserved. Reproduction for personal or classroom use only. (moon) facing it. From Earth, we see half of the light side and half of the dark side during this phase so sometimes it is called a “half moon.”

Waxing Gibbous As you continued to turn to the left, the light shone on more of the side of the orange you could see, lighting up all of the orange except for a small crescent. This is the waxing gibbous phase.

Full Moon Once you had turned halfway around so that the lamp was directly behind you, the light (sun) shone directly on the orange (moon) making the whole side facing you bright. This is a full moon. During a full moon, the side facing away from Earth is dark. This phase is the exact opposite of new moon.

(Note: if the orange isn’t fully illuminated, try moving your head or shoulders so you aren’t blocking the lamp. If you are blocking it, you’ve created a lunar eclipse – which happens when the Earth blocks the sun’s light from hitting the moon. Normally, the moon is just above or just below Earth so an eclipse doesn’t happen every time there is a full moon.)

Waning Gibbous At this point, the amount of the light side of the moon that we can see begins to decrease, or wane. The next phase is called waning gibbous. Most of the moon is still light during this phase.

Last Quarter Next is the last quarter (also called third quarter) where only half of the illuminated side of the moon is visible. This phase is opposite of first quarter. Notice that your back is facing toward the direction you were facing when you saw the first quarter phase!

Waning Crescent The last visible phase is the waning crescent, where only a sliver of light is visible. This phase is opposite the waxing crescent. After this, you will be facing toward the lamp (sun) again, and the orange (moon) will be back to the new moon phase! 41 how to make 3d glasses project

WHAt YOu NEED:  3D glasses template  Scissors (see next page)  X-acto knife  Printer & printing paper  Clear tape  Cardstock  Anaglyph images**  Red & blue cellophane

2. Trace the images onto the cardstock and cut it out.

3. Carefully cut out the “lens” holes using the X-acto knife. (Get an adult’s help.)

4. Cut cellophane squares slightly larger than your lens holes. (Note: You may use a plastic baggie colored with red and blue marker instead.)

5. Tape the red square over the left eye hole and the blue over the right.

6. Tape the earpieces onto the eyepieces.

7. Use your 3D glasses to view special 3d images, called anaglyphs!

WHAT HAPPENED: Humans have binocular vision, meaning we have two eyes. Since our eyes are each positioned differently in our heads, each sees a slightly different perspective. But when used together and aided by our brains, we end up perceiving depth and notice even more details due to something called binocular summation. Using 3D glasses and specially designed images called anaglyphs, we can recreate a similar viewing effect.

Anaglyphs are pictures made by superimposing two images of the same object (taken from slightly different perspectives) in two complementary colors—usually red-blue. When viewed with spectrally opposed glasses, like the ones you just made, the anaglyph appears three-dimensional. In this case, the red filter over the left eye perceives the red in the image as white and the blue within the image as black. The right eye sees just the opposite, perceiving red as black and cyan as white. Through the 3d glasses, the graduations between red and cyan are viewed as graduations of bright to dark, lending the perception of depth. When viewed together, the brain fuses the images into one, three-dimensional view. 42 3d glasses template

RED GEL BLUE GEL

43 Fireworks and chemistry Science Lesson 1. chemistry of fireworks Last time you watched a fireworks display, you probably saw an exciting combination of colors and sparks. Did you wonder just how this amazing pyrotechnics display worked? There’s a lot of chemistry involved in creating good fireworks!

One of the key ingredients for firecrackers, ground fireworks, and aerial fireworks (ones which explode in the sky) is black powder. It was invented by the Chinese about 1000 years ago. It’s a blend of potassium nitrate (saltpeter), charcoal, and sulfur in a 75:15:10

ratio. Black powder is used to launch aerials and also causes the explosions necessary © Home Science Tools. All rights reserved. Reproduction for personal or classroom use only. for special effects like noise or colored light.

In sparklers, black powder is mixed with metal powders and other chemical compounds in a form that will burn slowly, top to bottom. In simple firework rockets, black powder is confined in a tube around a fuse. When lit, the powder creates a force that results in an equal and opposite reaction. This pushes the firework off the ground and causes the compounds inside it to explode in the air. More complex fireworks shells are launched from a mortar, a tube with black powder that causes a lift-off reaction when lit. The firework shell’s fuse is then lit as it goes up into the air, and at the right time an explosion inside the shell causes its special effects charges to burst.

2. The Color of Fireworks The bright, colorful part of the fireworks display is caused by “excited” electrons in the atoms of different metal and salt compounds. These compounds are in little balls called stars, made of a similar compound to what makes a sparkler work. Different metals burn in different colors. For example, if a copper compound is lit, its flame will be a blue-green color. Calcium burns red-colored and potassium burns purple. In fireworks, metals are combined to create different colors.

When the star compounds inside a firework are heated, the excited atoms give off light energy. This light falls into two categories: incandescence and luminescence. Incandescence is light produced from heat. In fireworks, reactive metals (aluminum or magnesium) cause a burst of very bright light — sometimes at temperatures over 5000° F! Compounds that are less reactive don’t get as hot, resulting in dimmer sparks. Luminescence, on the other hand, is produced from other sources and can occur even at cold temperatures.

The electrons in the compound absorb energy, making them “excited.” The electrons can’t maintain this high level, though, so they jump back to a lower level. They release light energy (photons) in the process. Barium chloride gives fireworks a luminescent green color, and copper chloride makes a blue color. For either kind of light, it’s important to use pure ingredients since traces of other compounds will obscure the color.

44 properties of metal Science Lesson For most people, metal is another word for iron, steel, or a similar hard, shiny substance. But does this definition fit with the true properties of metals? Yes… and no. Before we explain, you should know that most of the elements in the periodic table are metals. Metals are found in the center and left side of the periodic table. They can be further classified as alkali metals, alkaline earth metals, transition metals, and basic metals.

1. Metals Science Lesson An element is a substance made up of one kind of atom; it cannot be separated into simpler parts. For example, the element helium (think hot-air balloons) is made up exclusively of © Home Science Tools. All rights reserved. Reproduction for personal or classroom use only. helium atoms. Elements are generally classified as metals or nonmetals (although some elements have characteristics of both; these are called metalloids).

2. Three properties of metals are: Luster: Metals are shiny when cut, scratched, or polished.

Malleability: Metals are strong but malleable, which means that they can be easily bent or shaped. For centuries, smiths have been able to shape metal objects by heating metal and pounding it with a hammer. If they tried this with nonmetals, the material would shatter! Most metals are also ductile, which means they can be drawn out to make wire.

Conductivity: Metals are excellent conductors of electricity and heat. Because they are also ductile, they are ideal for electrical wiring. (You can test this using some household items. Keep reading to find out how!)

3. Additional Properties of Metals High melting point: Most metals have high melting points and all except mercury are solid at room temperature.

Sonorous: Metals often make a ringing sound when hit.

Reactivity: Some metals will undergo a chemical change (reaction), by themselves or with other elements, and release energy. These metals are never found in a pure form, and are difficult to separate from the minerals they are found in. Potassium and sodium are the most reactive metals. They react violently with air and water; potassium will ignite on contact with water!

Other metals don’t react at all with other metals. This means they can be found in a pure form (examples are gold and platinum). Because copper is relatively inexpensive and has a low reactivity, it’s useful for making pipes and wiring.

45 properties of metal science lesson - page 2

4. Five groups of metals: Noble Metals are found as pure metals because they are nonreactive and don’t combine with other elements to form compounds. Because they are so nonreactive, they don’t corrode easily. This makes them ideal for jewelry and coins. Noble metals include copper, palladium, silver, platinum, and gold.

Alkali Metals are very reactive. They have low melting points and are soft enough to be cut with a knife. Potassium and sodium are two alkali metals. © Home Science Tools. All rights reserved. Reproduction for personal or classroom use only. Alkaline Earth Metals are found in compounds with many different minerals. They are less reactive than alkali metals, as well as harder, and have higher melting points. This group includes calcium, magnesium, and barium.

Transition Metals are what we usually think of when we think of metals. They are hard and shiny, strong, and easy to shape. They are used for many industrial purposes. This group includes iron, gold, silver, chromium, nickel, and copper, some of which are also noble metals.

Poor Metals are fairly soft, and most are not used very much by themselves. They become very useful when added to other substances, though. Poor metals include aluminum, gallium, tin, thallium, antimony, and bismuth. 5. Alloys: Strong Combinations The properties of these different metals can be combined by mixing two or more of them together. The resulting substance is called an alloy. Some of our most useful building materials are actually alloys. Steel, for example, is a mixture of iron and small amounts of carbon and other elements; a combination that is both strong and easy to use. (Add chromium and you get stainless steel. Check your kitchen pots and pans to see how many are made from stainless steel!)

Other alloys like brass (copper and zinc) and bronze (copper and tin) are easy to shape and beautiful to look at. Bronze is also used frequently in ship-building because it is resistant to corrosion from sea water.

Titanium is much lighter and less dense than steel, but as strong; and although heavier than aluminum, it’s also twice as strong. It’s also very resistant to corrosion. All these factors make it an excellent alloy material. Titanium alloys are used in aircraft, ships, and spacecraft, as well as paints, bicycles, and even laptop computers!

Gold, as a pure metal, is so soft that it is always mixed with another metal (usually silver, copper, or zinc) when it’s made into jewelry. The purity of gold is measured in karats. The purest you can get in jewelry is 24 karats, which is about 99.7% pure gold. Gold can also be mixed with other metals to change its color; white gold, which is popular for jewelry, is an alloy of gold and platinum or palladium. 46 properties of metal science lesson - page 3 6. Metal from Ore Ores are rocks or minerals from which a valuable substance – usually metal – can be extracted. Some common ores include galena (lead ore), bornite and malachite (copper), cinnabar (mercury), and bauxite (aluminum). The most common iron ores are magnetite and hematite (a rusty-colored mineral formed by iron and oxygen), which both contain about 70% iron. There are several processes for refining iron from ore. The older process is to burn iron ore with charcoal (carbon) and oxygen provided by bellows. The carbon and oxygen, including the oxygen in the ore, combine and leave the iron. However, the iron does not

get hot enough to melt completely and it contains silicates left over from the ore. It can be © Home Science Tools. All rights reserved. Reproduction for personal or classroom use only. heated and hammered out to form wrought iron. The more modern process uses a blast furnace to heat iron ore, limestone, and coke (a coal product, not the soft drink). The resulting reactions separate out the iron from the oxygen in the ore. This ‘pig iron’ needs to be further mixed to create wrought iron. It can also be used for another important purpose: when heated with carbon and other elements, it becomes a stronger metal called steel. Considering the process involved, it’s not surprising that iron was not used until around 1500 BC. But some pure metals – gold, silver, and copper – were used before then, and the alloy bronze is thought to have been discovered by the Sumerians around 3500 BC. But aluminum, one of the most essential metals in modern use, wasn’t discovered until AD 1825, and wasn’t commonly used until the 20th century! 7. Corrosion: Process & Prevention Have you ever seen a piece of silver that lost its shine, or iron with reddish-colored rust on it or even holes in it caused by corrosion? This happens when oxygen (usually from the air) reacts with a metal. Metals with a higher reactivity (such as magnesium, aluminum, iron, zinc, and tin) are much more prone to this kind of chemical destruction, or corrosion.

8. properties of metal rust When oxygen reacts with a metal, it forms an oxide on the surface of the metal. In some metals, like aluminum, this is a good thing. The oxide provides a protective layer that keeps the metal from corroding further. Iron and steel, on the other hand, have serious problems if they are not treated to prevent corrosion. The reddish oxide layer that forms on iron or steel when it reacts with oxygen is called rust. The rust layer continually flakes away, exposing more of the metal to corrosion until the metal is eventually eaten through. One common way to protect iron is to coat it with special paint that keeps oxygen from reacting with the metal underneath the paint. Another method is galvanization: in this process, steel is coated with zinc. The oxygen, water molecules, and carbon dioxide in the air react with the zinc, forming a layer of zinc carbonate that protects from corrosion. Look around your house, yard, and garage for examples of corrosion as well as galvanization and other means of protecting metal from rust. 47 homemade ice cream in a bag

WHAt YOu NEED:  1/2 cup milk  2 cups ice  1/2 cup cream  1/2 cup rock salt  1/4 cup sugar  1/2 cup table salt  1/2 teaspoon of vanilla  quart sized freezer ziplock bag or other flavoring  gallon sized freezer ziplock bag

WHAT YOU DO: © Home Science Tools. All rights reserved. Reproduction for personal or classroom use only. 1. Stir the milk, cream, sugar and flavoring together in a bowl, then pour the mixture into a quart-size freezer ziplock bag. Close the bag.

2. In the gallon-sized ziplock bag put about 2 cups ice and 1/2 cup salt. Stick the quart-sized bag inside a gallon-size ziplock, half-filled with ice and rock salt.

3. Salt lowers the freezing point of water, which causes the ice to melt at a lower temperature. The lower freezing point provides the temperature difference needed to transfer heat between the freezing ice cream ingredients and the melting ice. Rock salt doesn’t lower the freezing point as much as table salt does (so it results in smoother ice cream, because it freezes more gradually), but for this activity you can try table salt. Use a thermometer to measure the temperature in the outer bag.

4. Next, begin shaking the bag so that the ingredients are whipped together. What do you expect to happen to the cream mixture? After five minutes of shaking, let the bag sit for a few minutes.

5. Now take the temperature inside the gallon bag again. Has it changed? What happens if you don’t shake it?

6. When the ice cream is thick, get out a spoon and enjoy!

WHAT HAPPENED: Ice cream is a colloid, an emulsion where two substances are just suspended within each other rather than being chemically bonded together. This is why many ice creams also have an emulsifier to prevent the fat molecules from separating from the rest of the ice cream (this makes the texture of the ice cream smoother). Ice cream also uses a stabilizer (like gelatin or guar gum) to help hold air into the ice cream, which gives it its light texture. To be officially called ice cream, the colloid has to be at least 10% milk fat and 6% non-fat milk solids (such as proteins).

48 how to make a fire extinguisher

WHAt YOu NEED:  Empty soda bottle  5 tablespoons of vinegar  1/2 tablespoon of baking soda  Tea light candle

In order to put out a fire, one of three things must be removed © Home Science Tools. All rights reserved. Reproduction for personal or classroom use only. from it: heat, fuel, or oxygen. Knowing this, firefighters don’t always use water to put out a fire. safety note WHAT YOU DO: Ask an adult 1. Light the candle. for permission 2. Pour the vinegar into the bottle and add the baking soda. before lighting (You may want to use a funnel.) The mixture should fizz. the candle!

3. Hold the bottle sideways over the lighted candle, making sure no liquid escapes.

4. What happens to the flame?

WHAT HAPPENED: The baking soda and vinegar react to make carbon dioxide, a gas that is heavier than oxygen. As it ‘pours’ out of the bottle, it pushes the lighter oxygen away from the candle. The fire, now deprived of oxygen, can no longer burn.

49 discovering flaming colors of fireworks Have you ever watched a fireworks show and wondered how all the different colors — amazing reds, yellows, oranges, blues, purples, greens, and more — are made? The color, or colors, that a firework makes depends on what color-producing chemicals are in the firework. These chemicals are various metal salts that burn when the firework goes off, and burning the metals is what makes the colors. Different metals give off different, specific colors. In this science activity, you will get to burn some metal salts at home to investigate what colors they make. Then, at the next fireworks show, you can impress friends and family with your knowledge of what may be causing some of the colors they see!

WHAt YOu NEED: © Home Science Tools. All rights reserved. Reproduction for personal or classroom use only.  Table salt (technically called sodium chloride.)  Copper sulfate is available through pet or aquarium stores to combat algae, or through home improvement stores as a root killer. Make sure the product is pure copper sulfate and that it is in powder or small crystals form. (Alternatively, if you would like these chemicals plus two other colorful, hard-to-find metal salts and some safety equipment all in one convenient package, try the Rainbow Fire Kit from our partner Home Science Tools.)  Small plastic bag  Bamboo skewers (at least 6)  White glue  Candle  Matches or lighter  Container of water  An outdoor surface you can safely burn a candle on when it is dark outside (or twilight). Be sure it is in an open area to allow good air flow.  Adult helper

Recommended:  Disposable gloves, dish-washing gloves are a fine alternative. These are for handling the copper sulfate.  Safety goggles  Flashlight  Masking tape and pen or marker to label the skewers with the chemical names

50 discovering flaming colors of fireworks - page 2

Prep Work: When you burn the skewers, be sure to do it in an open, outdoor area and be careful not to breathe the fumes or smoke from the skewers. Adult supervision is needed when using fire, burning the skewers, and handling the chemicals.

If you want, label the skewers with the names of the chemicals that you will be coating the skewers with. (If you are only testing table salt and copper sulfate, you will not need to label

the skewers since it is easy to tell the difference between these chemicals as table salt is © Home Science Tools. All rights reserved. Reproduction for personal or classroom use only. white and copper sulfate is blue.) You will be coating three skewers with each chemical. Make the labels by putting a piece of masking tape around the blunt end of the skewer, like a flag. With a pen or marker, write the name of a chemical name on each skewer’s masking tape label. what to do: 1. Pour a small amount of table salt (roughly one tablespoon) into a small plastic bag. Apply a thin layer of glue to the last one inch of the tip of a skewer. Just a little bit of glue is enough.

2. Dip the glue-coated tip of the skewer into the salt in the bag. Twist the skewer back and forth a bit to coat the skewer’s tip with the salt. Set the skewer aside to dry.

3. Repeat this process with two more skewers so you have a total of three skewers that have their tips coated with salt.

4. Next, have an adult coat three more skewers with copper sulfate. Read and follow all safety precautions on the packaging that the copper sulfate came in. Be careful not to let anybody breathe in any copper sulfate dust or get any on their skin or face. If desired, use disposable gloves and safety goggles. If not using gloves, be sure not to touch the copper sulfate. Coat the last one inch of the tip of a skewer in a thin layer of glue and dip the glue-coated tip into the bag of blue-colored copper sulfate, twisting it back and forth to coat the tip in copper sulfate.

5. Repeat this with two more skewers so that you have three total that are coated in copper sulfate. If you are using the Rainbow Fire Kit, repeat this process to have an adult coat other skewers with any additional chemicals you want to test (i.e., strontium chloride or boric acid). Be sure to follow all proper safety precautions when handling these chemicals. Coat three skewers with each chemical you want to test.

6. Allow all of your skewers to dry. This will take about half an hour for each. When it is dark (or twilight) outside, take your candle, matches, and prepared skewers to an open area outside where you can safely burn a candle. Be sure there is good air flow. Also have a container of water with you as a safety precaution.

Disclaimer: Science Buddies participates in affiliate programs with Home ScienceTools, Amazon.com, Carolina Biological, and Jameco Electronics. Proceeds from the affiliate programs help support Science Buddies, a 501(c)(3) public charity, and keep our resources free for everyone. Our top priority is student 51 learning. If you have any comments (positive or negative) related to purchases you’ve made for science projects from recommendations on our site, please let us know. Write to us at [email protected]. discovering flaming colors of fireworks - page 3

7. Have an adult light the candle. Once the candle is burning well, carefully take out one of the prepared skewers and hold the chemical-coated end in the flame. Be sure not to breathe the fumes or smoke from the burning skewer! think about: What color does the chemical burn? How does it compare to the normal color of the candle’s flame? Tip: You may be able to see the chemical’s color in the candle’s flame, or by holding the

skewer away from the candle (once the chemical has caught on fire) and looking at the © Home Science Tools. All rights reserved. Reproduction for personal or classroom use only. flame on the chemical-coated end of the skewer. The skewer may also catch fire after a few moments. Simply remove it from the flame and blow it out, or extinguish it in the container of water. Repeat this process for the other chemical-coated skewers. (To help you distinguish which chemical you are burning, remember that the skewers coated in table salt will have white- coated tips, while the skewers coated in copper sulfate will have blue-coated tips.) think about: Which color does the table salt (sodium chloride) burn? Which color does the copper sulfate burn? If you burn other chemicals, what color(s) do they burn? cleanup: Be sure to extinguish the candle and the skewers when you are done with the activity. When you are sure they have been extinguished, you can dispose of the used chemical coated skewers in the garbage. What Happened? A typical flame will burn yellow/orange with a little bit of blue near the base of the wick. When you burned the skewer tip coated with sodium chloride, you should have seen that the flame on the sodium chloride was pure yellow/orange (without any blue).This is because when the metal sodium is burned, it makes intense yellow/orange light. When you burned the skewer tip coated with copper sulfate, you should have seen that the flame gained blue-green traces. This is because when the metal copper is burned, it makes bluish-green light. If you tested additional chemicals from the Rainbow Fire kit, you should have seen that the boric acid burned a vivid green and the strontium chloride burned red. Today when we watch fireworks displays there are many colors represented but this was not always the case. From the time fireworks were invented (the earliest documentation is from around the 7th century C.E. in China) until the 1830s, all fireworks were either white or orange. Then, in the 1830s, the Italians discovered that adding metal salts to the fireworks mixture resulted in interesting colors, just like in the flame test in this science activity. 52 how to make quicksand

WHAt YOu NEED:  Spoon  Cornstarch  Water  Plastic mixing bowl

We’ve all seen the movies where adventurers are making their way through a jungle, and one steps into quicksand and is quickly sucked down beneath the surface. But what is © Home Science Tools. All rights reserved. Reproduction for personal or classroom use only. quicksand and how does it trap people?

Quicksand occurs when the right type of sand becomes super-saturated with water. Sand often becomes super-saturated with water when it is deposited in a sink hole or hollow in the ground that is made out of material (such as clay) that does not allow the water to drain from the sand. The sand and water make a soupy mixture that often looks solid on top, but when it is agitated (by being stepped on) it turns into a liquid. The most likely places to find quicksand are along beaches, lakes, rivers, marshes, and swamps because there is a ready supply of water there. However, quicksand can also be formed by underground springs or runoff water from heavy rains.

Making real quicksand can be tricky. The grains of the sand need to be round in shape and the same size. Ordinary playground sand (the type you can buy in a store) rarely meets this standard. Since quicksand is normally found along beaches, marshes, and other wet areas, if you can find sand here, you probably have sand with the right grain type to make quicksand.

A much easier and more dependable way to make ‘quicksand’ is to use cornstarch instead of sand.

WHAT YOU DO: 1. See how quicksand behaves in the plastic mixing bowl, combine small amounts of water and cornstarch together to form a mixture that looks like heavy whipping cream and has the consistency of honey. The approximate ratio of the cornstarch-water mixture is 1-1/4 cups of cornstarch to 1 cup of water. So if you use a regular sized box of cornstarch (about 16 oz), you will use about 1-1/2 to 2 cups of water.

2. After making your mixture, gently lay your hand on the surface of the cornstarch- water mixture. You should notice that your hand sinks in the mixture like you would expect it to do. Move your hand through the mixture, slowly first and then trying to move it really fast. Was it easier to move your hand slowly or quickly through it? If your mixture is deep enough to submerge your entire hand in it, try grabbing a handful of the mixture and pulling your hand out quickly. Then try again, this time relaxing your hand and pulling it out slowly. Did you notice a difference? 53 how to make quicksand - page 2

3. Try punching the cornstarch-water mixture. (Be careful not to hurt yourself on the bowl!) Make sure to hit the substance hard and pull your fist back quickly. Did the substance splatter everywhere or did it stay put in the bowl? (If it splattered, add more cornstarch.)

what happened: Whenever you gently and slowly moved your hand through the cornstarch-water mixture, it behaved like a liquid. But when you tried to move your hand through it © Home Science Tools. All rights reserved. Reproduction for personal or classroom use only. quickly or hit the substance very hard, it behaved like a solid. Weird, huh? But the way this cornstarch-water mixture behaves is very similar to how quicksand behaves.

The way that a liquid flows or moves is affected by its viscosity. Quicksand and the cornstarch-water mixture are both non-Newtonian fluids, meaning that their viscosity changes with the type of force applied to it. Unlike quicksand, the viscosity of Newtonian fluids (fluids, such as water and honey, that follow Sir Isaac Newton’s law of viscosity) is dependent only on the temperature and pressure of the fluid, not the force applied to it. For instance, warm honey flows much more freely (less viscous) than cold honey (more viscous).

Since the ability of a non-Newtonian fluid to move depends on the force or stress applied to it, these fluids do not act like ones we are more familiar with (e.g. water). A light pressure, such as pouring or gently pressing the cornstarch-water mixture, allows it to move like a liquid. But a high pressure, such as punching firmly, causes the cornstarch-water mixture to act as a solid. This same principle applies to quicksand. When it is lightly stepped on by the unaware adventurer, the quicksand liquefies and the foot of the adventurer starts to sink. Panicking, the adventurer tries to quickly pull his or her foot out, only to find that now the quicksand is acting like a solid, encasing the foot all the more firmly in this unpredictable substance.

But don’t worry about getting sucked down into quicksand like you see in the movies. Although humans do initially sink when they first enter quicksand, they cannot sink all the way (only to about chest deep). This is because humans are less dense than quicksand. One way to get out of quicksand is to lay back on it and float, much like you would do in regular water. If you have just a foot stuck in quicksand, gently move the foot back and forth, adding water along the side of your leg. This will help the quicksand to act more like a liquid and release your foot.

54 how to make a light fountain

WHAt YOu NEED:  A clear water bottle  Pencil  Duct Tape or  Flashlight aluminum foil and tape  Sink or basin  Thumb tack or push pin  Adult supervision

This experiment demonstrates how light travels within water. Have you ever seen a

colored light show, where the fountains of water are colored? The Light Fountain you © Home Science Tools. All rights reserved. Reproduction for personal or classroom use only. make in this project is a smaller version of those large fountains. Do you have a Christmas tree that has small lights in the branches? Those are fiber optic lights, and the way light travels through the fiber is just like the way it travels through your water fountain! WHAT YOU DO: 1. Remove the label from the water bottle. Cover half (vertically – from opening to bottom of bottle) of the water bottle using duct tape or taping on aluminum foil.

2. Use the thumb tack to poke a hole through the duct tape on the bottle, about two inches from the bottom of the bottle.

3. Use a pencil or similar object to enlarge the hole. Always have an adult supervise the use of sharp objects!

4. Fill the bottle with water, keeping your thumb over the hole so the water stays in. In a very dark room, hold the water bottle over the sink or basin. Shine a flashlight through the uncovered side of the bottle toward the hole where the water is coming out.

5. Watch as the stream of water forms an arc that the light follows down into the sink. Try making the water stream a different color by putting colored cellophane in front of the flashlight lens.

WHAT HAPPENED: The light beam travels through the stream of water, even when the stream bends, as it does in this experiment. The light beam bounces off the walls of the water stream and follows it to the end. This is called internal reflection. The light ray inside the stream of water behaves as it would inside an optical fiber. Optical fiber works like this: you send a light beam into one end of the fiber and it comes out the other end, even when it bends, just as light travels through the stream of water in your experiment.

55 how to make a kaleidoscope

WHAt YOu NEED:  Three small mirrors that are  Overhead transparency or approximately the same size. plastic page protector  Thin cardboard  Candy sprinkles or  Tape colored paper

Like a microscope or telescope, the optics in a kaleidoscope are used to enhance our vision in some way. Vision depends on light, and optics are used to control light by © Home Science Tools. All rights reserved. Reproduction for personal or classroom use only. reflecting or bending it so that we can see in different ways. Kaleidoscopes use mirrors to reflect light into beautiful shapes and patterns.

WHAT YOU DO: 1. Tape the long edges of the mirrors together so that they form a pyramid shape, with the reflecting sides of the mirrors all facing inward.

2. Next, cut out a triangle of thin cardboard to fit one end of the kaleidoscope and tape it on. Use a sharp pencil to poke a hole in the center of the cardboard, to serve as a peephole.

3. Cut two triangles of a transparent substance, like a plastic overhead transparency, to fit the other end; tape up two of the edges to form a three-sided envelope, and put candy sprinkles and/or bits of colored paper inside. Tape the third side closed, then use tape to attach the envelope to the end of the kaleidoscope.

4. Now, look through the end that has the peephole and aim the kaleidoscope at a light source. The colored objects on the other end will reflect off of the mirrors into star- shaped patterns.

5. You can also study reflection using two small square glass mirrors taped together on one side. Stand them upright and spread them apart like an open book, so that a small object can be placed between them without touching on either side. How many reflections do you see? Now, lay a pencil in front of the mirrors so that it touches on each side. How many pencils are reflected? Experiment with moving the mirrors closer to and further from each other; how does the number of reflected objects change in relation to the angle of the mirrors?

56 how to make a mini hot air balloon

WHAt YOu NEED:  Hot air balloon flight  Lighter  Aluminum foil (for the basket)  Adult supervision  Birthday candles (for the fuel) and common sense  Scissors  Plenty of indoor space  Ultra-thin garbage bag (like those  String (if flying your balloon lining office trash cans and those in a space where it can travel that dry cleaners use*) beyond your reach)  Plastic straws (for the frame) *If using a dry cleaner’s bag, you’ll

Learn about air density as you make a simple hot air balloon in this easy science project. In its simplest construction, a hot air balloon is comprised of an envelope (the balloon part), a basket, and a fuel source. We’ll show you how to construct an envelope from a super-lightweight trash can liner and fuel your balloon with birthday candles.

FIRE SAFETY: Although this project uses only birthday candles, which even very young children put their faces near when blowing them out on birthday cakes, always exercise extreme caution and utmost common sense when experimenting near an open flame. Make sure there are no flammable liquids nearby, and keep a fire extinguisher or smothering method within reach at all times. Never experiment with fire without adult supervision. WHAT YOU DO: 1. Cut a 4 x 4″ square of aluminum foil. This will be your “basket.” 2. Use the lighter to melt wax from the bottom end of the candle so it forms a pool about 1″ in from the corner of the aluminum foil. Before the wax hardens, press the end of the candle into the melted wax and hold it in place until the candle stands upright on its own. It may take a few tries. 3. Repeat with the remaining candles, placing them 1″ in from the other three corners. Be gentle with the baskets, as too mush jostling will dislodge the candles. If this does happen, simply melt more wax and secure the candle in place again. 4. Fold the edge of the aluminum foil in 1/4 to 1/2 inch, forming a ‘wall’ to contain the wax as it burns, so it won’t drip outside the basket. 5. Measure the width of your bag’s opening and determine how long your straw frame should be. We simply estimated and used trial and error until our frame fit snugly inside the bag’s opening. 6. If using flexible straws, cut off the bendable part so only the straight section remains. You’ll need to fasten the straws into two pieces of identical length for the frame. Each of ours had three straws connected together. 7. To connect the straws, cut a small slit (about 1/4 inch) at the bottom of one straw then insert another straw into the cut end of the first. The slit will make the connection stronger, but secure it with tape for added rigidity, using as little tape as possible. 57 how to make a mini hot air balloon - page 2

8. Repeat for the second half of your frame. 9. Find the middle of your straws and tape them together in an “X,” again using as little tape as possible. Place the “X” frame snugly inside the bag’s opening. Using as little tape as necessary, secure it in place. 10. Staggering the straw frame and the candles (so the candles aren’t directly above the straws), tape the basket onto the frame with the candle wicks pointing up into the envelope. If you’re flying your balloon in an area where it can travel beyond your reach, tie string to the basket, so you can harness it during its flight. 11. Take your hot air balloon to an open, mostly empty room to fly it. (You may try it outside, but even © Home Science Tools. All rights reserved. Reproduction for personal or classroom use only. days that don’t seem windy usually have too much breeze for a balloon like this to fly.) Have an adult help you launch the balloon. Have one person hold the closed end of the bag up and away from the basket while the other lights the candles. A lighter with a long stem, like an Aim ‘n Flame, works best. Continue holding the bag until it fills with air and stands on its own. After a minute or so, it should lift off the ground.

what happened: One of the important properties of gas is that it expands when it gets hot and contracts when it cools. This means that when a gas is heated, the individual molecules that form it move faster and spread further apart from each other. As a result, the gas also gets lighter as it gets hotter, since the molecules are less densely concentrated.

The expanding property of gas is what enables hot air balloons to inflate and fly. Hot air going into the balloon has a less dense concentration of molecules, making the inflated balloon lighter than the cooler, denser air surrounding it. That denser outer air buoys up the balloon and allows it to float. Conversely, the affect of cooling air will bring the balloon back down—the air molecules inside the balloon move closer together when cooled, making the air in the balloon no longer lighter than the surrounding air. That’s why a cold, damp cloud or fog can be dangerous for a hot air balloon pilot.

Although air might seem weightless, it’s actually formed by gases and has mass like any other matter. Usually air is made up of 78% nitrogen, 21% oxygen, and 1% carbon dioxide and noble gases. The density of air is about 0.075 pounds (or approximately 34 grams—a little more than an ounce) per cubic foot at 70 °F and one atmosphere of pressure. That’s why using lightweight materials was so vital in building this hot air balloon. The weight of the balloon and the air inside it has to be less than the weight of the displaced ambient air in order for it to fly. Tips & tricks: If your balloon fills but won’t lift off, it may be too heavy. Try cutting the birthday candles in half and carefully stripping the wax at one end to reveal the wick: Partially cut through the candle (not completely through) then slide the scissors off, using the blades to scrape away the wax, exposing the wick. Or, instead of traditional birthday candles, use the skinniest ones you can find. Painters plastic is the right thickness for your balloon, but you’ll have to figure out a way to fasten it into an envelope.

58 solar purifier

WHAt YOu NEED:  Water  Plastic wrap  Salt  Masking tape  Large bowl  Rock  Short glass or beaker. (or other small weight)

When water evaporates from the ocean, it leaves salt behind. If you had no fresh © Home Science Tools. All rights reserved. Reproduction for personal or classroom use only. water to drink, you could distill (or purify) ocean water by taking advantage of evaporation. Here’s how:

WHAT YOU DO: 1. Add salt to two cups of water and stir until it dissolves, then pour it into a large bowl.

2. Place a short glass in the middle of the bowl. (This glass should be shorter than the rim of the bowl, but taller than the level of the saltwater.)

3. Now cover the bowl with plastic wrap, taping the edges, if necessary, to get a tight seal. Place a small rock or other weight on top of the plastic directly over the glass in the bowl. This helps you collect the distilled water in the glass.

4. Put the bowl outside in the sun. Leave it for several hours, or for the whole day. When you check it again, there will be water in the cup. Taste it to find out of it’s salty or fresh! (You can also use electricity to test it for saltiness by making a saltwater circuit.)

WHAT HAPPENED: The sun warmed the water in the bowl until it evaporated, becoming a gas. When the gas rose and hit the plastic it condensed there in droplets (just like water vapor condenses into clouds). The droplets rolled down the plastic toward the weight and eventually fell into the glass (like rain falling from the sky). The salt was left behind in the bowl, making the water in the glass pure enough to drink.

59 scavenger hunt ideas

Who doesn’t love a scavenger hunt? Get your kids outdoors this summer and ‘scavenging’ for treasures in nature. Armed with a list of items to find, they’ll eagerly look at the world around them with more observant eyes. Nature watching will be exciting as they collect specimens, take pictures of animals, and do fun activities. This is a great afternoon project for a group of kids, or it can be expanded into a summer-long family project with siblings and parents working together to create fun displays with the results of their summer’s explorations. Use these ideas to get you started designing your own

scavenger hunt that is a good fit for your location. © Home Science Tools. All rights reserved. Reproduction for personal or classroom use only. Planning a Scavenger Hunt Your scavenger hunt can be as simple or as elaborate as you wish to make it. As you plan, consider carefully your location, the participants, and how long the hunt should last.

1. Location. Choose items for the scavenger list that the kids will most likely be able to find. If they are hunting in a local park, for example, don’t ask them to find leaves from trees that don’t grow there. For a summer-long hunt, your kids will look in many different locations, and it isn’t necessary to plan these out ahead of time. If you are going out of town on a family vacation, though, you could do a little internet research to find out what kinds of trees and flowers are common in the area you are traveling to. It’s a good idea to lay some ground rules first, as some places (such as certain national parks) don’t allow you to pick any wildflowers, and it’s illegal to collect feathers from some species of birds, etc.

2. Participants. Design your scavenger list with the ages of the participants in mind. Younger kids may get frustrated if the items on their list are too hard to find, while older kids will enjoy the challenge. If you are working with a large group, form teams and let younger kids work with older kids. Decide whether your hunt will be a contest or not— some kids enjoy competition more than others. If your group is well-suited to it, have a prize for the person who checks the most things off the scavenger list. (Here are some inexpensive science gift ideas.)

3. Duration. Have a manageable list for the amount of time you have to work with. If you only have an hour or two, just make a list of things each participant needs to look for. For a longer-term project, include things to collect, activities to do, and things to photograph.

60 planning a scavenger hunt - page 2 Scavenger Hunt ideas The possibilities for a nature scavenger hunt are endless! The following are some ideas to get you started designing your own scavenger list:

Things to See  Insects, such as a butterfly, dragonfly, grasshopper, and beetle.  A spider web.  Leaves from an oak or maple tree.

 Frogs, toads, and lizards. © Home Science Tools. All rights reserved. Reproduction for personal or classroom use only.  Wildflowers.  Mushrooms (do not eat wild mushrooms! They are difficult to identify other than by experts.)  Wild berries (do not eat them unless they’ve been identified as non-poisonous!)  Find feathers or abandoned birds’ nests.  If you’re by the ocean, look for seashells and seaweed.

Things to Collect  Pinecones, dandelions, seeds.  Encourage identification skills by having the kids find different types of leaves or flowers native to your area. (Look for regional field guides in your local library or on enature.com, or do an internet search for the ‘native plants’ of your state.)  Collect ferns, moss, pinecones, seeds, thorns, and other botanical specimens.  Catch butterflies, capture a ladybug, dragonfly, or other insects, find a cocoon or chrysalis (see this article for butterfly-hatching instructions).  Look for fossils, colored rocks, quartz, or flat skipping stones.  Find a temporary ‘pet,’ such as a frog, snail, or grasshopper. (You should let them go after you’ve observed them.)  Look carefully for something ‘camouflaged,’ such as a walking stick insect or a moth that blends in with its surroundings.  If you live on the coast, include things like seashells, seaweed, small crustaceans, and small pieces of driftwood.

Things to Do  Go wading, swim in a lake, climb a tree, go on a picnic.  Draw a flower, make a dandelion chain, make a leaf rubbing.  Get up early to watch the sun rise, write a description of a sunset.  Go hiking, build a shelter, find your way with a compass.  Look at pond water under a microscope, go stargazing with binoculars or a telescope.  Record a birdsong or other animal sounds. 61 planning a scavenger hunt - page 3  Find a chrysalis and watch a butterfly emerge from it.  Go to the zoo and have each child find a fact about their favorite animal.  Keep a nature journal for writing descriptions of activities and drawing pictures.

Things to Photograph  Birds at a bird bath, bird feeder, or bird house.  Squirrels or other small animals.  Animal tracks (if you have time, you can also make a plaster cast).

 Sunset or sunrise. © Home Science Tools. All rights reserved. Reproduction for personal or classroom use only.  Waterfall, mountain, boulder, lake, beach, or swamp (with someone in the picture!)  A sibling or friend doing one of the activities listed under ‘things to do.’  Unusual sights like a tree root curled around a rock.  The discovery (plant, animal, landscape) that amazed you the most.

Make a Display Encourage kids to keep a nature notebook with a record of everything they saw on their nature explorations. Their notebook can include pressed flowers and leaves, pictures they took with a disposable camera, written descriptions, drawings, and more. Let them display three-dimensional objects in a display case or keep them in their own decorated cardboard nature box. Items such as seashells and rocks can make an attractive decoration in a glass jar. Insects can be pinned and labeled to be kept either on a piece of corrugated cardboard, or in a more permanent and attractive exhibit case. After hunting all summer, they should have quite a satisfactory collection!

Nature Tools Before setting out on a nature expedition, gather a few important tools from around the house:  Plastic bags – bring home specimens without making a mess.  Camera – take pictures of what can’t be collected with a digital or disposable camera.  Notebook and pens or colored pencils – make notes and drawings so you can remember what you see.  Jars – transport insects and other small critters, or use to display rocks and shells  Snack – hunting can work up an appetite!  Sunscreen and bug repellent – don’t get burned and bitten.  Baby wipes or hand sanitizer – clean up when you get grimy.

62 planning a scavenger hunt - page 4

Kids don’t need lots of fancy equipment to observe nature, but here is a list of suggested tools to make their study even more rewarding:  Insect net – catch butterflies and other flying insects.  Binoculars – observe birds and squirrels up close.  Magnifying glass – see the intricate details on insects, flowers, leaves, and more.  Plant press – preserve flowers and leaves to mount in a notebook or use for cards or crafts.  Field guides – get help identifying trees, flowers, rocks, birds, etc.

 Backpack – carry all your exploration tools conveniently. (If you’d like a backpack © Home Science Tools. All rights reserved. Reproduction for personal or classroom use only. already stocked with high-quality nature exploration tools that will last for years, see our line of nature backpack kits.)  Scavenger Hunt Activities

Listed below are a few examples of activities that you could develop based on your location. Park Scavenger Hunt Instructions: The items on this list should be easy to find in a city park. Bring along an empty egg carton to collect your finds. (Note: for kids who aren’t able to read yet, try a color scavenger hunt—paint the inside of each cup of an egg carton a different color and let kids collect anything they can find that matches each color.)  Something Green  Something Red  Something Smooth  Something Rough  Something Fuzzy  Something Round  Something Straight  Something That Rattles Or Makes A Sound  Two Different Kinds Of Leaves That Are Different Colors  A Pine-cone  A Flower  A Rock With An Interesting Pattern

Backyard Scavenger Hunt Instructions: Using sidewalk chalk, write a list of items for kids to find. Draw a square or circle next to each item where they can place the actual objects as they collect them. Customize the items on the list to include things you know exist in your backyard—some may be easy to spot and others should require a little more scavenging! Include multiples of objects; Example:  5 small pebbles  3 pine-cones  4 yellow flowers  2 large leaves, etc. 63 Nature scavenger hunt Circle what you saw on your scavenger hunt, then color the page. © Home Science Tools. All rights reserved. Reproduction for personal or classroom use only.

Did you see anything else? Draw and color it here.

64 sun prints

WHAt YOu NEED:  Dark colored construction paper  Tape  Pencil  Solid objects with interesting  Scissors shapes that you can trace  Repositionable glue around (leaves, buttons, coins,  Window that gets lots of sunlight and plastic toys work well)

You can make fun pictures using the sun’s power to fade the color from construction © Home Science Tools. All rights reserved. Reproduction for personal or classroom use only. paper! You could also do the project by setting objects on your paper and laying it flat in the sun instead of using the special repositional glue. WHAT YOU DO: 1. Trace around your objects on construction paper and cut out each shape. Or, you can draw your own shapes and cut them out. Be creative! You could even draw letters to spell your name. 2. Arrange the paper shapes onto a new sheet of dark-colored construction paper to make a design. Use the repositionable glue to stick each shape to your picture. Don’t use much glue though, or it will be hard to peel your shapes off later. 3. Turn the shapes towards the window and tape the corners of your picture to the window to hold it in place. 4. Leave your picture in the window for a couple days or until you notice that the color of the construction paper has started to fade. (Compare it to a new piece of the same color of paper to see if it has changed.) When it is quite a bit lighter than it was when you started (it might take up to a week; it depends on how many sunny days you have!), untape the picture from the window and peel off the shapes. They should come off pretty easily, but do it slowly to make sure your picture doesn’t tear.

WHAT HAPPENED: Have you ever left an art project made from construction paper in the sun for too long? If so, you probably noticed that the color started to fade and the paper ended up a lot lighter than it once was. In this project, you covered parts of the paper with paper shapes, then when you left your picture in the sunlight, it started to fade. Since the shapes blocked sunlight from hitting the parts of the paper they covered, you could see the original color of the paper after you peeled off the shapes! The extra layer of paper from the shapes protected those parts of the paper from the sun’s rays that faded the color from the rest of the sheet of paper. Sunlight contains ultraviolet (or UV) rays – the same rays that will give you a sunburn if you are in the sun for too long without sunscreen on. Those rays cause chemical reactions in the dye that gives construction paper its color. When the paper absorbs the rays of light, a chemical reaction breaks down the dyes so they aren’t as bright. UV rays can lighten a lot of things. Some people’s hair turns a lighter color when they are in a lot of sunlight. Hanging white laundry outside in the sun to dry can make it look whiter also. To make prints like this in just a few minutes you can get a Sunprint Kit that contains special colored paper. 65 water wheel project In this project, you’ll make a replica of a water wheel.

WHAt YOu NEED:  Corrugated cardboard  Protractor or six inch diameter or foam board round object to trace  Flat top push pins,  Scissors or box cutter finishing nails, sewing pins  Ruler or a hot glue gun  String  Pen or pencil  Tiny bucket (like an egg carton  Wooden skewer section used to hold an egg) © Home Science Tools. All rights reserved. Reproduction for personal or classroom use only. Note: To just see the general principal of a water wheel at work with a one time experiment, you can use cardboard and white glue. If you would like your water wheel to last under numerous experiments in the water, go for the more water proof option by using foam board and pins. Hot glue is waterproof and can be used in place of the pins if making the foam board water wheel.

Water wheels (or waterwheels) convert the energy from falling water into power that can be used to do work. Agricultural communities in the past used water wheels to grind grain, saw wood, and pump water. spinning water wheel. (They’re still used today in developing countries and communities that shun technological advancements.) Water wheels have a set of paddles mounted around a central wheel. The falling water is transmitted to another machine by the wheel’s shaft or rotating element. It works like a gear. Water wheels were used to grind grain, saw wood, and pump water.

WHAT YOU DO: 1. Make a straight line two inches from the edge of the foam board, down one short side of the foam board or cardboard. Divide this section into ten 1.5 inch segments. These will be your paddles.

2. Using the protractor, trace out two circles on the foam board, marking the center of the circle using your protractor. This is where your axle will connect the two halves of your water wheel. (The axle is the shaft that the wheel rotates on.)

3. To make the stand for your water wheel, you may consider tracing this pattern. Just click on the link to download and print it. The size of this pattern works best for a water wheel with a 6 inch diameter (the size made with a 6 inch long protractor). Cut out the pattern along the solid black lines, NOT along the dotted lines. Trace two of the legs on the foam board, and two of the support beams. (The support beam is the rectangle.)

4. Cut out the water wheel pieces from the foam board or cardboard with scissors or a box cutter. Have an adult help you!

5. On one of the halves of the water wheel, use the protractor to mark the placement of the paddles at about 40 ° intervals. Angle the paddles toward the center of the wheel like the spokes of a bicycle. 66 water wheel project - page 2

6. Use glue or pins to attach the short end of the paddles so that they line up on the markings on the wheel. Attach the other half of the water wheel to the paddles.

7. Carefully insert the skewer through the centers of the wheels. Set the water wheel aside.

8. To make the stand for the water wheel, take one leg and use pins or glue to attach the support beams to the leg at the dotted lines. Take the other leg and attach it to the

support beams opposite of the first leg. To increase support for your stand, you can © Home Science Tools. All rights reserved. Reproduction for personal or classroom use only. attach the optional base to the bottom of the stand.

9. Place the water wheel on the stand, with the axle (skewer) resting in the grooves at the top of the stand.

10. Place your water wheel in the kitchen sink. Open the faucet so that a small amount of water runs out and spins the wheel. Experiment with the placement of the wheel under the stream of water and the amount of water coming out to see what works best.

11. Watch your water wheel at work by attaching a bucket to the axle. Punch holes into the top of the egg carton section with a skewer so that a piece of string can be looped through to make a handle.

12. Attach a larger piece of string from the handle of the bucket to the axel of the water wheel. Experiment with how much weight can be lifted in the bucket using the power of water.

67 planning science camp Planning a Summer Science Camp

The Basics Age Range The ideal age to begin camp is five years old, but teaching a wide range of ages works in this situation. I have successfully taught children ranging from 2-9. It is possible to find activities that are enjoyable for each child, including a mix of science and art, but also a © Home Science Tools. All rights reserved. Reproduction for personal or classroom use only. challenge. Don’t expect your 6-year-old to get the same out of science camp that your 12-year-old does. Rather, play to their individual interests and strengths.

Schedule The ideal camp runs for five days, for about four hours each day. It’s a good idea to feed the children lunch at the culmination of camp as that is a positive time together to review the day. We have food that reminds us of what we have learned. This is one of the children’s favorite parts. We also use this time to review concepts and give out rewards. Remember when scheduling to include the following; • Each day requires 15-30 minutes set-up. • Clean-up (with the children helping with some of it) may take 30 minutes each day. • Be flexible: Take bathroom and drink breaks. Expect a few mishaps and time needed to comfort a child or clean-up between activities.

Science Topics Choose a subject you and the children are interested in and desire to know more about. Here are some examples of themes you could choose from: • Insects • Weather • Ocean Animals • Space • Biomes • Rocks and Minerals

Another approach is to teach a unit study each day. Here’s an example: Day 1: Earth Day 2: Rocks Day 3: Plants Day 4: Animals Day 5: Weather

68 planning science camp The Basics

Organize and Plan The best way to get this all accomplished in 4 hours a day is to have everything prepared ahead. You’ll want to have everything you’ll need for each day gathered, sorted and cut out each day cut out ahead of time. It is also a good idea to set aside the entire week so © Home Science Tools. All rights reserved. Reproduction for personal or classroom use only. that each evening you can clean up and be ready for the next day. Then cut up all the food for the following day’s lunch and make any preparations I need. The Details Timeline • We would recommend beginning the day with prayer and a song that you will sing all week. You can then introduce the subject in a fun way. For example, when studying biomes you could bring out plastic animals for the children to sort. • Next, we begin a lesson that is age appropriate. The older students will be writing vocabulary and definitions. The younger children will have an age appropriate activity. • Then take part in an art activity together that teaches about the science topic. An example is to make stars with glitter on paper when studying astronomy. The art project will represent the different intensities of heat (red, blue and white). • Give your children a break that includes exercise. Water play is usually part of this activity on a hot day! • We come back to finish work, add to a science notebook page, or create a new art project that reinforce the science topic. • A planned activity or just play time is welcomed while I prepare the lunch. We then have lunch together with review and rewards. You can give rewards for good behavior and working hard all morning. At the end of the week, you can give small rewards such as a gummy bear for each question they are able to answer.

How to Prepare for Science Camp I spend countless hours collecting materials, but I must add it is so enjoyable and fun to think of interesting ways to introduce a subject. You may choose to teach a topic where the work is already done for you (by using a unit study, for example). For older children, you may choose to utilize this time to perform specific experiments you did not have time to do during the year.

69 planning science camp The Basics

Recommended Timeline: • Choose your topic and begin research through books and the internet. Make sure we have plenty of pictures from magazines, books and I save pictures on Pinterest. • Next, pull your resources together to form an outline of what you want to teach each day and write daily lessons. • Then use the internet to help find creative food ideas to enhance the learning.An example is the planets lunch or owl sandwiches we had (both ideas found on Pinterest). The internet also helps develop creative art projects that go along with the lessons, such as keeping biome notebooks or making marbled planets. • Once the plan is in place, begin gathering my supplies for the food and projects. • Then put the supplies for each day into separate boxes and label them (for example: Day 3, Jungle). • Utilize spare time to create backgrounds needed for a mural, cut arrows needed for a cycle, print materials and generally have all the projects ready. Examples of Science Camp Plans Rocks and Minerals Day 1: Introduction to minerals. This will include showing examples (mineral specimens or pictures). The snack and food will include these minerals as well. Cheese is an excellent example of the mineral calcium. We will review what calcium, the mineral, looks like from our picture or sample.We will then go on a hunt for rocks out of doors. Each child will have a cloth bag to collect what they find. We will come back and wash up and have a snack. We will then continue learning through the art activity. We will have also learned about crystals in the introduction and so we will start to make our own crystals (that will be ready by Day 5). The rest of the week we will learn about the rock cycle and each type of rock and will have food and activities to reflect that. An example is a sandwich for sedimentary rocks. Dessert may be ice cream with hard shell topping to represent igneous rock. The review consists of questions related to what we learned. The questions may be as simple as “What did we learn about today?” Have students name three igneous rock examples. Or ask, “What is the difference between a sedimentary rock and a metamorphic rock?”

Forest Biomes Day 1: Ocean Day 2: Rainforest Day 3: Desert Day 4: Savanna/grasslands Day 5: Forest At the end of the week you may decide to take the children to a special place that relates to what they learned all week. Grandparents may enjoy being involved during the week as well as on the field trip. If you have been studying biomes, a trip to the beach or a walk in the forest would be fun. If you are studying space, an evening with a telescope would enhance learning.

With these tips and examples, We hope you will discover the delight of teaching children science by having a camp this summer! 70 71