Grade 8 Structures and Mechanisms

Grade 8: Structures and Mechanisms

GRADE 8: STRUCTURES AND MECHANISMS ACTIVITY #1: INTRODUCTION: PLACEMAT

Curriculum Expectation: 3.1 Preparation Time: 15 min. Lesson Duration: 1 x 70 min. period Purpose: Diagnostic Assessment of prior knowledge

Materials: Chart paper Markers

Method: Teacher Preparation Chart paper is used as Placemats. The paper is divided into four sections. Prepare 5-10 Placemats on chart paper depending on class size. (You want groups of 4) Place one Placemat at each station with several coloured markers. Write one of the following statements in each section on the Placemat.

Statements:  What is a system?  Name some natural systems and their function/purpose.  Name some man-made systems and their function/purpose.  What are the parts of a system?

Delivery method:  Divide students into groups of 4.  Give brief introduction to topic.  Explain Placemat activity. . Students sit in groups of four with a prepared sheet of chart paper in front of them. . Each student takes a different colour marker. . Students are given 5 minutes to respond to the question or statement in front of them. . After 5 minutes, they will rotate the sheet one turn clockwise so that each student is facing a new question. . Repeat this process until all questions/statements are answered by every student. . Each group presents their responses to the class. . Teacher emphasizes, facilitates, corrects assumptions and ensures that all key ideas are addressed.

Assessment:

This is a diagnostic assessment. Because every student within a particular group writes with a different colour marker, the teacher can review the responses and easily identify the ideas contributed by each student.

1 Grade 8: Structures and Mechanisms

GRADE 8 STRUCTURES AND MECHANISMS ACTIVITY #2 SCRAPBBOOK Curriculum Expectation: 1.1, 1.2 Preparation Time: 30 min. Lesson Duration: 1 x 30 min. period Purpose: To increase scientific literacy and to develop an understanding of STSE issues prior to Town Hall Forum Materials: Sample newspaper articles Markers Student handouts (4 of General questions to guide the writing of summaries per student, 2 of Summary Organizer per student) Method: Teacher Preparation Regularly read the newspaper and select articles that concern the affects of mechanization on society/communities locally and internationally. Prepare a sample scrapbook Delivery method Introduce students to reading the paper, discuss issues, perspectives and critically analyzing what the article is about. Model using the scrapbook worksheets (below) to summarize individual articles and to synthesize major themes (NOTE: this requires teacher has chosen articles for model scrapbook with care). Remind students you will provide a limited number of worksheets to each student. Assessment: See attached rubric: student scrapbooks will be collected and assessed.

Name:______STUDENT ASSIGNMENT At the beginning of the Systems in Action unit you will start a scrap book of newspaper articles concerning the pulp and paper industry. The articles could be about plant closures, the impact of pulp and paper on the environment, new technologies and trade disputes. As well, articles regarding immigrant challenges in finding employment should be included. You may include other articles that you think are relevant and that you are able to connect to an issue from the scenario. You are expected to collect a minimum of 10 articles. With permission of the teacher, the internet may be used if not enough print articles can be found. Articles must be referenced and attached in the scrap book. You will write a short summary (2-4 sentences) of the main idea of each article and your reaction to the article. List any new vocabulary that you needed to learn in order to understand the article.

3 Grade 8: Structures and Mechanisms Name:______General questions to guide the writing of the summaries: Question Jot Notes What is the issue?

What are the relevant facts related to the issue?

What kind of information is given to support the various views? (Facts, statistics, testimonials etc.) How is the information presented?

What biases might the author have?

What information is missing?

What is your personal opinion/perspective of the article and of the larger issue?

Who are the stakeholders?

Which stakeholders stand to gain/lose the most if their view is accepted?

4 Grade 8: Structures and Mechanisms Summary Organizer of Scrapbook Articles Name: Article Title, Date and Main Points in Article How do main points support/refute Synthesis of main points from articles Reference citizen’s perspective that support/refute perspective 1

Scrapbook Rubric

Criteria Level 1 Level 2 Level 3 Level 4 Score Selection of Fewer than 6 articles 6-9 articles collected. Some 10 articles collected. More than 10 articles Articles collected. Relationship to related to issues in scenario Articles relate clearly to collected. All articles issues unclear issues in scenario relate clearly to all issues K/U in scenario. Additional connections recognized /4 Interpreting and Main issues not well Main issues somewhat Main issue usually Main issue always Applying Concepts identified. Few relevant identified. Relevant facts identified. Relevant facts identified. Relevant facts facts stated only partially stated clearly stated stated with exceptional K/U clarity /12 Demonstrates how Uses article with limited Uses article with moderate Uses article effectively. Uses article highly Article Supports effectiveness. Examples are effectiveness. Examples are Provides clear examples. effectively. Provides or Refutes unclear. somewhat clear examples of high clarity Perspective T/I /12 Connections to Synthesizes incomplete Synthesises partially Synthesises complete Synthesises multiple larger Issues/Other connections complete connections connections complete connections Issues A /12 Organization, Writing is unclear. Writes with limited clarity. Writes clearly. Most Writes with considerable Vocabulary, Vocabulary used incorrectly. Vocabulary used with vocabulary used clarity. Vocabulary used Spelling and Many significant limited correctness. Some correctly. Few correctly and accurately. Punctuation spelling/punctuation errors spelling/punctuation errors spelling/punctuation No spelling/punctuation errors errors C /4 TOTAL: /44

GRADE 8 STRUCTURES AND MECHANISMS ACTIVITY #3: WEBQUEST

Curriculum Expectations: 2.6, 3.1, 3.2, 3.3, 3.4, 3.5, 3.6 Preparation Time: 20 min. Lesson Duration: 3 x 70 min. periods

Purpose: Through a WebQuest, the students will have the opportunity to review the important characteristics of systems and simple machines in preparation for Activity #6 (Build a Machine). Much of this information will be review of material learned in prior grades (e.g., simple machines are covered in Grades 2 and 4). The WebQuest will also introduce students to the concepts of work and mechanical efficiency, as well as the related mathematical formulae. Finally, through the WebQuest, students will learn the nature of the rich performance task that they will be asked to complete in Activity #6. The WebQuest is intended to engage students who respond well to the use of technology.

Materials: computers (e.g., laptop cart) WebQuest booklets (pages9-15 of this unit plan) pens or pencils

Method:  The teacher will arrange the students into pairs. The teacher can either assign partners or let the students choose for themselves, depending on what works best in a particular class.

 The teacher will hand out the WebQuest booklets (see Appendix) and explain that the class will be doing a WebQuest in order to research important concepts concerning simple machines. If any students are unfamiliar with the term WebQuest, the teacher will explain that, using the questions in the booklet to guide their research, they will visit a series of predetermined websites to gather information.

 The teacher will tell students to pay careful attention to the characteristics of simple machines, because the WebQuest will lead into an activity in which they will be asked to build a machine.

 Once the students are seated at computers, the teacher will tell students to open the internet browser and to follow the instructions on the first page of the booklet. The teacher will advise the students that the initial website has been bookmarked on their computers: http://jango1963.googlepages.com/understandingstructuresandmechanisms

Teacher Preparation: The WebQuest has previously been created and is available online. To reduce the amount of time wasted searching for the starting website on the internet, the teacher

7 Grade 8: Structures and Mechanisms should make an effort to bookmark this site on the student computers prior to the start of class. Prior to the start of this activity, the teacher should visit the “Teacher Page” link available on the initial website and download a copy of the WebQuest booklet. Copies of this booklet would then need to be photocopied for the students to use. The teacher will also need to schedule enough computer time for the students to complete this task.

Finally, before starting this activity with the students, the teacher should quickly go through the WebQuest to make sure that all of the websites can be accessed via school computers. Assessment: Performance on this activity will be assessed using a checklist. The checklist will be used to document completion of the WebQuest activity and to keep a record of learning and social skills. Each student will receive a copy of the checklist which will allow them to assess their own performance and that of their partner. There will also be a column for the teacher to record his/her own impressions.

A BLM of the checklist is given at the end of this lesson (page16 of unit plan).

Accommodations: If needed, the teacher may pair students of varying levels of ability together in order to assure success. For example, an ELL learner would be paired with a technologically savy student. In the case of a student with visual deficits, a partner could be asked to read the material to him/her; in addition, worksheets with large print would be provided.

References: Ministry of Education and Training. (2007). The Ontario curriculum, Grades 1 – 8: Science and technology. Toronto: Queen’s Printer for Ontario.

Ministry of Education and Training. (2002). The Ontario curriculum – Exemplars Grades 7 and 8: Science and technology. Toronto: Queen’s Printer for Ontario. http://camillasenior.homestead.com/Review_Simple_Machines.pdf http://camillasenior3.homestead.com/mechanicalefficiency.html http://www.ftschool.org/fourth/science/simple_machines.html http://sln.fi.edu/qa97/spotlight3/spotlight3.html http://edheads.org/activities/simple-machines/glossary.htm

GRADE 8 STRUCTURES AND MECHANISMS Grade 8 WebQuest – Understanding Structures and Mechanisms Let’s Save Bosco!

To begin…

1) You will need to work with a partner. Once you have found a partner logon to a computer and start up the internet browser.

2) Go to http://jango1963.googlepages.com/understandingstructuresandmechanisms

3) Click on “Go to next page…” and read about Bosco the Elephant’s unfortunate situation.

4) Click on “Your task:” and to find out how you can help Bosco.

5) Before you can help Bosco, you need some background information. Click on “Let’s get started!” Answer the questions in this booklet as you work your way through the WebQuest.

Background Information – Systems in Action

This unit is called “Understanding Structures and Mechanisms – Systems in Action” but what exactly is a system? Follow the link to Wikipedia

(http://en.wikipedia.org/wiki/system). Focusing mainly on the “Overview,” “System concepts,” and “Types of systems” sections, answer these questions:

1) Define the term system.

2) Take a moment to discuss with your partner what you’ve learned about systems. Give an example of:

i. a man-made system

ii. a sociocultural system

iii. an economic system

iv. a natural system

Background Information – Simple Machines

To help Bosco, you will need to build a mechanical system that will include two or more simple machines. To get the necessary background information, continue with the WebQuest and answer the questions below:

3) Define the following terms:

a. simple machine

b. compound machine

c. energy

d. force

e. load

f. effort

4) Complete the following table. For each type of simple machine, draw a picture and give a brief description. Also, for each machine name at least two common items that are examples of that type of machine.

Simple Picture Description Examples Machine Pulley

*** Please name, draw, and briefly describe all four types of pulleys. Use the back of the page if necessary. Lever

***please name, draw, and describe all three types of levers. Use the back of the page if necessary.

Inclined Plane

Wheel and Axle

5) Why do we use simple machines? How do they help us in our day-to-day activities? If I use a simple machine to complete a task (e.g., using a wedge to help split a log of wood), am I doing less work? Justify your answer.

6) Define the term work and give the mathematical formula that can be used to compute “work.”

7) Define the term mechanical advantage. How do we calculate mechanical advantage?

Assessment Checklist for WebQuest Activity Please use this checklist to assess (i) your performance and (ii) the performance of your partner on the WebQuest. In the table below, fill in the “self” and “peer” columns using a number from 1 to 3 (“1” = not at all, “2” = sometimes, “3” always). The teacher will record his/her comments in the final column. For the question marked by an asterisk (*), circle “Y” for yes or “N” for no. Rating of Skill or Ability Rating of Self Teacher Partner You (or your partner) remained focused on the task at hand (i.e., the WebQuest)? You (or your partner) only visited websites necessary to complete the WebQuest. You (or your partner) followed directions.

You and your partner worked together effectively as a team. The volume and tone of your voice were appropriate for the activity (i.e., working on a computer with a partner) We completed the WebQuest Y / N Y / N Y / N booklet.* I feel comfortable with the Rating and Rating and Rating and material about systems and Comments: Comments: Comments: simple machines explored in the WebQuest.

GRADE 8 STRUCTURES AND MECHANISMS ACTIVITY #4: HANDS-ON CENTRES

TEACHER NOTES Overview of Enduring Understandings: Structures and Mechanisms (K-8) Grade 1 Grade 2 Grade 3 Everyday structures Movement Strong & Stable . Objects have observable . Movement is a change in Structures characteristics and are made position of an object . A structure has both from materials . Mechanisms contain one or form and function . Materials have specific more simple machines within . Structures are affected properties them, and enable objects to by the forces acting on . An object is held together by move them its structure; its materials . Simple machines and . Structures need to be and structure determines its mechanisms make life easier strong and stable to be purpose and/or more enjoyable for useful . Humans make choices humans related to their use of objects & materials that have a direct effect on the environment Grade 4 Grade 5 Grade 6 Pulleys and Gears Forces Acting on Structures and Flight . Pulleys and gears are special Mechanisms . Flight occurs when the kinds of wheels and axles . Different forces have different characteristics of used to meet a variety of effects on different structures structures take needs and mechanisms advantage of certain . Pulleys and gears can be . The types of forces acting on a properties of air used to make work easier structure or mechanism . Air has many and/or faster, including influences their design properties that can be changing speed, direction, . Forces acting on structures and used for flight and for and/or force of movement mechanisms can be identified, other purposes measured and countered . Forces that result from natural phenomena have an effect on society & the environment Grade 7 Grade 8 Form & Function Systems in Action . Structures have a purpose . Systems are designed to . The form of a structure is accomplish tasks dependent on its function . All systems include an input and . The interaction between an output structures and forces is . Systems are designed to possible optimize human and natural resources Enduring understandings form the basis of what students should already know (prior knowledge). Curriculum Expectations 3.5 Understand and use the formula work=force X distance to establish the relationship between work, force, and distance moved parallel to the force in simple machines 3.6 Calculate the mechanical advantage (MA=force needed without a simple machine/force needed with a simple machine) of various mechanical systems Preparation Time: approx. 2 hours Lesson Duration: 2 x 70 min. period

SIMPLE MACHINES HISTORICAL PERSPECTIVE: By the first century BC, most fundamental mechanical devices had been invented. Ancient Greeks listed five (wheel & axle, wedge, lever, pulley, and screw). Other things such as gears, chain wheels (e.g. bike chains), and cams were also known, but considered variations of the lever. Apart from the screw, ancient Chinese also invented all these mechanisms. All basic mechanisms were known over 2,000 years ago. Since then, very few new mechanisms have been added to this list. (From the Invent a Book of Mechanisms)

Purpose (Overall): . to provide kinaesthetic learners with meaningful activities . to give students the opportunity to understand and calculate mechanical advantage and work Purpose (Specific): LEVERS PURPOSE: To get some first hand experience with levers. To introduce the idea of experimental error. To apply what they know/learn about levers to a very common situation weighing something. If you use rulers, they have to be the thick wooden kind that won't bend under these loads. There are flat sticks in the kit to use in place of rulers. You must use hexagonal pencils; the lever tends to roll off of the round ones thereby changing the results. Questions to encourage teaching points: . What happens when the fulcrum is directly in the middle of the ruler? Is it easy to move your object? . Is the force you use equal, greater or less than the weight of the object? . How about when the fulcrum is closer to your object? Does it get easier or harder to move your object as the ruler moves across the fulcrum (so that the object is closer to the fulcrum)? . What happens to the distance or height that you can raise your object as the fulcrum is moved closer to the object? . What happens if you move the fulcrum far away from the workload (object)? Is the force you use equal, greater or less than the weight of the object? . Is there any mechanical advantage of doing this? . Can you find any parts of your body that can act like a lever?(Arms & legs are examples of 3rd class levers)- For further study – proceed to the nearest playground with a friend or friends to investigate the mechanical advantage provided by a seesaw! INCLINED PLANES PURPOSE There are many different forms an inclined plane can take. Inclined planes are all around us. They are basically a triangular shaped object that changes a vertical force into a horizontal one or vice versa. Inclined Plane 1: A screw is a type of inclined plane. We start with what is obviously an inclined plane and turn it into a screw. In the case of a screw (an inclined plane wrapped around a rod or axle), the rotational motion (let's say horizontal) results in linear motion (vertical). Inclined Plane 2: Wedges are another very common form of inclined plane. They look more like an inclined plane. But many things are wedges that we don't recognize as such, knives for instance. Look at the blade of a knife in cross section and it looks like a wedge; you push down (vertically) on the knife and the butter (or whatever) spreads apart into two pieces (horizontally). Most screws are "right-hand" screws. They turn counter clockwise to open. The one notable exception that we probably all have come across is the left pedal on a bicycle. It is a "left-hand" screw. Otherwise, the pedal would unscrew as you were riding. The term "right-hand screw" comes about because if you curl the fingers of your right hand in the direction the screw is turning, your thumb will point in the direction the object will move.

WHEELS PURPOSE To reinforce that there are many types of wheels such as pulleys and gears. GEARS PURPOSE Gears 1: An introduction to gears and terminology. Let the students become familiar with how to set them up and use them. The focus is on the direction of rotation. Give the students a chance to analyze their data and deduce the fact that whether or not the follower turns in the same direction as the driver depends only on if there's an odd or even number of gears in between. The students are asked to make a prediction. Presumably they will find that their rule applies independent of the size of the gears. Gears 2: In this experiment, we look at the speed of gears of different sizes and derive the concept that, regardless of size or shape, if the driver turns the distance of one tooth, the adjacent gear will also move exactly one tooth. So, if the driver has 20 teeth (small gear) and the follower 40 (medium gear), you must turn the driver two times around (20 + 20 teeth) to get the follower to turn one time around. There's another chance in this experiment to analyze data graphically, to deduce the rule being followed and then apply the rule to a new situation. Gears 3: There are so many types of gears and gear combinations. This experiment introduces the crown gear and a real application of what the kids have learned. They get to design their own machine and then build it. Challenge: Since the driver and the follower have the same number of teeth in each of these drawings, it doesn't matter what is in between. The follower will always turn one time. PULLEYS Notes There is friction between the rope and the pulley wheel. If the load is too light weight, this friction tends to control the outcome of the experiment. An 8 oz. (approximately 227 g) can of condensed soup is just about right for a load. PURPOSE Pulleys 1: Pulleys can help us by making it easier to lift things or lower them. They can also redirect forces. For example, you might pull the rope horizontally as in Pulleys 2 but the load is still lifted up. Pulleys also let us move loads in places we might otherwise not be able to. For example, it would be difficult to stand on the top of a flag pole and pull the flag up. But using a pulley allows us to stay safely on the ground. Pulleys 2: This experiment introduces the very important concept of conservation of energy: if you exert less energy, the job is easier but less work will be done. This is shown here and later on in levers in that fewer weights are needed to lift the load but it doesn't go as high. See answer sheet to questions below MOTION COMMOTION PURPOSE: The purpose of this section is to allow students the opportunity to construct a contraption and to apply what they have learned about simple machines prior to undertaking the rich performance task. In addition, there are opportunities to integrate the Structures and Mechanisms unit with Visual Arts.

Materials: LEVER MATERIALS levers (wooden rulers)- enough for every student 2 pennies for each student 2 stickers for each student 1 fulcrum (pencil) enough for every student 10 weights/ group of 4 students

INCLINED PLANE MATERIALS (for every 2 students) 1 piece of paper 1 pencil per student Scotch tape Highlighters and scissors -1 per groups of 4

WEDGE MATERIALS(for every 2 students) 2 wood blocks per groups of 4 1 fat wedge per groups of 4 1 skinny wedge per groups of 4

GEAR MATERIALS(for every 2 students) 1 set of gears 2 labels

PULLEY MATERIALS(for every 2 students) 1 board and pulley 15 weights 1 rope 1 small bucket 1 pulley 1 load 1 large bucket 1 clamp2 hooks

Motion Commotion Design Challenge Materials: Each team of two to three will have: . One set of plastic K’nex™ and/or 1 set plastic Tinker Toys™ . A small bell . General supplies available to everyone (from long table on side of room): Balloons, Rubber bands, Paper cups, Dowels, Wooden skewers, Film canisters, String, Tape, Drinking straws, Pipe cleaners, Cardboard/heavy paper, Paper towel rolls, Toilet paper rolls, Springs, Marbles, Ping pong balls, Clothespins, Plastic spoons, Foam pipe insulation Student research station . Mouse Trap™ board game . Frigits™ construction kit . Magnetic Gears ™ (optional) . Book: Rube Goldberg: Inventions (optional) . Book: Gizmos & Gadgets: Creating Science Contraptions That Work (& Knowing Why) Various household objects that are simple machines (with labels indicating which simple machines) . Various K’nex toy creations (optional)

Method: Teacher Preparation: Collect materials for centres Create worksheets for students (as there are 22 pages per set suggest sending pages to printing services of school board) Delivery method:  Divide students into groups of 2-3  Give overview of centers including brief description of all unit activities and their relevance to each other  Indicate approximate time per station (approximately 10 minutes plus rotation time) and method to rotate through stations

 Provide each student with one copy of student worksheets. These also serve as study notes and must be cared for. No additional copies will be available from the teacher because of the length of each copy.

Assessment: Observation of students using anecdotal notes and questioning individuals at the centers to assess understanding; observation of learning skills( engagement, on task behaviour,, independent and/or cooperative behaviour etc) Accommodations: Students who are struggling learners or ESL may be paired with other supportive students

MATH CONNECTION CALCULATING MECHANICAL ADVANTAGE: The mechanical advantage can be calculated for the following simple machines by using these formulas: Lever: MA = length of effort arm / length of resistance arm. Wheel and Axle: MA = radius of wheel / radius of axle Inclined Plane: MA = length of slope / height of slope Pulley: All pulleys have a fixed MA depending on the type. A pulley with one rope (single fixed pulley) has an MA = 1. A pulley with two ropes (single moveable pulley) has a MA = 2. A pulley with 6 ropes(block and tackle) has an MA = 4.

EXAMPLES OF SIMPLE MACHINES IN EVERYDAY LIFE: Levers--teeter totter, oar, rake, hoe, bat, pick, fork, screw driver, snow shovel, hammer, bottle opener, light switch, spatula, stapler, crowbar, scissors, car jack, etc. Screw--different sizes of screws for metal or wood, drill, meat grinder, bolts, nuts, corkscrew, swivel chair, jar lid, etc. Inclined plane (ramp)--ladder, escalator, hill, roller coaster, stairs, wheelchair ramp, gangplank, dump truck, unloading ramp, etc. Wedge- -paper cutter, scissors, crowbar, chisel, axe, prying tools, can opener, door wedge, pins, needles, nails, etc. Pulley- -fan belt, elevators, steam shovels, flagpole, clothesline pulleys, derricks, cranes, lifts, pulleys, gears, old-fashioned well, block and tackle, winch, wire stretchers, Venetian blinds, etc. Wheel and axle--windmill, bicycle, roller skate, vehicles, rolling pin, egg beater, helicopter, old- fashioned telephone dial, fishing reel, record player, tapes, door knob, pencil sharpener, bobbins, fans, casters, etc. PLEASE FIND AFTER THE STUDENT WORKSHEETS (pages22-44 of this unit plan):  PULLEYS AND LIFTING ANSWER SHEET  MECHANISMS LESSON STARTER  VOCABULARY  RESOURCES

Student Worksheets

LEVERS

BACKGROUND

Levers work by decreasing the effort force by increasing the distance an object moves. Levers do not decrease the amount of work, they just make it easier (increase mechanical advantage)

Work is the transfer of motion and is only done when force produces motion in the direction of the force

Force is measured in newtons (N). One N is about the weight of a 100g mass. Moving 1N weight a distance of 1 meter does 1J (joule) of work.

Work=distance x force

Mechanical Advantage- a comparison of the force produced by a machine to the force applied to the machine. The smaller the effort force, the greater the MA

MA = Load Force (FL) = Effort Arm Effort Force (FE) Load Arm

If MA is <1, then the load is moved with relatively small effort force

Force/Distance Tradeoffs You come into contact with force/distance tradeoffs in all sorts of simple machines. For example, a lever is an example of this phenomenon:

In this diagram a force F is being applied to the left end of the lever. The left end of the lever is twice as long (2X) as the right end (X). Therefore on the right end of the lever a force of 2F is available, but it acts through half of the distance (Y) that the left end moves (2Y). Changing the relative lengths of the left and right end of the lever changes the multipliers. http://www.glenbrook.k12.il.us/gbssci/phys/Class/energy/u5l1a.html If available in your class read about work and force on this website. Then try the quiz.

THREE CLASSES OF LEVER http://www.technologystudent.com There are three classes of lever and each class has fulcrum, load and effort which together can move a heavy weight.

CLASS 1

The workman uses a trolley to move the large packing case. The fulcrum is the wheel.

CLASS 2

The gardener uses a wheel barrow

to lift tools and garden waste. The load is in the centre of the barrow

CLASS 3

The fisherman catches the fish which becomes the load at the end of the lever. Draw your own examples of the three classes of lever. Think in terms of examples that you have used at home, work or school.

LEVERS 1 MATERIALS 1 ruler to use as a lever 2 pennies 1 hexagonal pencil to use as a fulcrum 2 stickers 10 weights PROCEDURE

1. Label one sticker "L" for load and stick it at the end of the lever with the smaller numbers. 2. Label the other sticker "F" for force and stick it at the other end of the lever. 3. Put the fulcrum in the middle of the lever at the 15 cm mark. 4. Put a load of one weight at the end of the lever marked "L". Put the load as close as possible to the end of the lever. Be careful that the fulcrum stays in place. 5. Apply a force by putting weights at the "F" end of the lever. Keep them as close as possible to the end and be careful that the fulcrum stays in place. Add enough weights to lift the load. If the load starts to lift, but then drops back, try adding 1 or 2 pennies to the force. The pennies help to make up for the fact that we can't put the weights and fulcrum in exactly the right places. 6. Record the number of weights you need to lift the load. You do not have to record any pennies you used. FULCRUM AT LOAD FORCE NEEDED 6 1

6 3 7. Repeat this for the different loads shown below. 8. Plot your data below and use this graph to predict how much force is required to lift a load of five weights: ______Try it: ______

LEVERS 2 MATERIALS  1 lever (ruler)  2 pennies  2 stickers  1 fulcrum (pencil)  10 weights PROCEDURE 1. Label one sticker "L" for load and stick it at the "2.5cm" end of the lever. Label the other sticker "F" for force and stick it at the "30cm" end. 2. Put the fulcrum at the 15cm mark of your ruler in the middle of the lever. 3. Put a load of one weight at the end of the lever marked "L". Put the load as close as possible to the end of the lever. Be careful that the fulcrum stays in place. 4. Apply a force by putting weights at the "F" end of the lever. Keep them as close as possible to the end and be careful that the fulcrum stays in place. Add enough weights to lift the load. Use one or two pennies if you need to. 5. Record the number of weights needed (but not the pennies). 6. Repeat this for the same load (2 weights) but with the fulcrum in different positions. Record your results. FULCRUM AT LOAD FORCE NEEDED 4 2

8 2 CONCLUSION Based on this experiment, what can you recommend about how to make it easiest to lift a load with a lever? ______

CHALLENGE You've got a massive stone to lift into place and plenty of people to help you, but all you get is a bunch of people grunting. What do you do? Turn to a lever, of course! Try your hand at investigating how levers make work easier. How can a lever be used to weigh something? Describe it below in words and pictures.

LEVERS 3 PROCEDURE Do this part individually.

1. Set up a lever by placing a ruler on top of the pencil as illustrated. The ruler acts as the two lever arms. The pencil that it pivots or balances on is called the fulcrum. 2. Place a load of five coins or washers (taped together in a stack) at one end of the ruler on the 2.5 cm (1 in.) mark. 3. Lift the load by pressing down at the opposite end of the ruler using one finger. Notice how hard you need to press to lift the load.

4. Change the position of the pencil and press to lift the load. Try several different positions. Each time notice how hard you press in order to lift the load. Questions Write your answers on a separate sheet. 1. Where is the pencil fulcrum when it feels easiest to lift the load? 2. Where is the pencil fulcrum when it feels hardest to lift the load? 3. Was there an instance when the load was lifted without any effort? 4. How can you explain this?

LEVERS 4 Do this part with a partner. PROCEDURE 1. Place the load at the 2.5 cm mark. Place the pencil fulcrum under the 15 cm mark. 2. As your partner presses down on one end, measure the distance the load is lifted up (d1). Next, measure the distance the other end of the lever moves as your partner presses down (d2). Draw a picture showing the distances and compare.

3. Move the fulcrum to a position where you have to push hard to lift the load. Again, measure the distance the load is lifted and measure the distance the other end of the lever moves down. Compare these distances. Draw a picture showing the distances that each end of the lever moves.

4. Move the fulcrum to a position where you only have to push lightly to move the load. Make the same measurements as above and draw your results. Questions Write your answers on a separate sheet. 1. Compare the distance the load was lifted when you pushed hard to when you pushed lightly. What do you notice? 2. What role does the fulcrum play in determining how much you have to push to raise the load? If you needed to lift a load of ten quarters using ten pennies as the force, would you place the fulcrum closer to the pennies or the quarters? Explain.

INCLINED PLANE 1 MATERIALS 1 piece of paper 1 pencil 1 piece of cellophane tape 1 highlighter 1 ruler 1 scissors PROCEDURE 1. Make an inclined plane by marking a piece of paper diagonally and color a wide stripe along the diagonal. 2. Cut the paper along the diagonal as shown in Figure 1.

3. Tape the paper to the pencil as shown in Figure 2. 4. Wrap the paper around the pencil. FIGURE IT OUT What type of machine did you just make? ______

INCLINED PLANE 2 MATERIALS  2 wood blocks  1 fat wedge  1 skinny wedge  1 ruler PROCEDURE 1. Put the blocks side by side on your desk. Use your ruler to measure how long the two blocks are. (See Figure 1.)

2. Record the length below. Remember to write the units. WEDGE LENGTH No Wedge

Skinny Wedge

Fat Wedge 3. Place the skinny wedge where the blocks meet and push down as shown in Figure 2. Now measure and record the length of the blocks. 4. Put the two blocks back together and repeat step 3 using the fat wedge. Measure and record the length of the blocks. QUESTIONS When you pushed down on the wedge, which way did the blocks move? ______How does the thickness of the wedge affect the movement of the blocks? ______

GEARS 1 INTRODUCTION Gears are just wheels with teeth. You can use gears to slow things down or speed them up, to change direction or to control several things at once. First we'll look at gears of the same size. MATERIALS  1 set of gears  2 labels PROCEDURE 1. Put one axle in each of the four small gears. 2. Find or make a mark on one tooth on each gear. 3. Use the stickers to label one gear as the driver, "D", and one as the follower, "F". We will use the driver to move the follower. 4. Put these two gears on the base board with the marked teeth touching. See Figure 1.

5. Turn the driver one complete time around in a clockwise direction. Watch the follower as you do. Record how many times the follower turns and in what direction. 6. Now put another gear between the driver and the follower as in Figure 2. Turn the driver as in step 5 and record what happens to the follower. 7. Finally, repeat this procedure with two gears between the driver and follower. See Figure 3

NUMBER OF GEARS TURNS DIRECTION IN BETWEEN

DEDUCTION

Look at your results. What pattern or rule can you deduce about how the follower gear will turn?

______

PREDICTION

Let's say that both the driver and the follower were medium sized gears. What do you think would happen if we turned the driver one time around in the clockwise direction? How many times do you think the follower will turn and in what direction?

______

GEARS 2 INTRODUCTION Gears aren't always the same size and don't always have the same number of teeth. Let's investigate what happens with different sized gears. MATERIALS  1 set of gears  1 ruler PROCEDURE 1. For this part of the experiment, we are going to use a small gear as the follower and a medium gear as the driver. Set them up on the base board with the marked teeth touching. 2. Turn the driver one time and record how many times the follower turns. 3. Next turn the driver 2 times and then 3 times and record how many times the follower turns. NUMBER OF TURNS NUMBER OF TURNS DRIVER FOLLOWER 1

5 4. Graph your results. 5. Use the ruler to draw a straight line through the points on your graph. The line should continue to the edges of the graph. 6. Use the graph to predict how many times the follower will turn if the driver turns 5 times: ______7. Try it and record your results. 8. You were probably able to predict very accurately how many times the follower would turn. Let's see if it has anything to do with the number of teeth. Start by counting the number of teeth on a gear of each size and record it below.

9. Use the same set up as before: a medium gear for the driver and a small gear for the follower. Turn the driver one time and record how many times the follower turns.

DRIVER FOLLOWER SIZE NUMBER OF TEETH NUMBER OF TEETH TURNS Large 20

Medium 20

Small 20 10. Repeat step 9 using a large size gear as the driver. 11. Finally, repeat step 9 using a small gear as the driver. DEDUCTION Can you detect a rule or pattern in your data that will help you predict how other combinations of gears will work? ______APPLICATION Try using your rule: if the driver is a small gear ( ___ teeth) and the follower is a large gear ( ___ teeth), how many times will the follower turn if you turn the driver three times? ______Now try it and see what happens: ______GEARS 3 INTRODUCTION There are lots of ways to combine gears. Let's look at a few more. MATERIALS 1 set of gears PROCEDURE 1. Try using a crown gear. Look at the set up shown in Figure 1 with two small gears at right angles to each other.

Predict what you think will happen when you turn the driver one turn in the clockwise direction. ______2. Build it and try it out. What happens? ______

A STORY You own a toy store and just got a large shipment of ice skates to sell. You want to make a display in your store window that shows two dolls, dressed up like ice skaters, spinning in place. You have one electric motor that will turn one doll but you'll have to use gears to make the second doll turn. Figure 2 shows how this works.

You build it and it works fine except that one doll spins clockwise and one spins counter clockwise. You want them to both spin the same direction. What can you do? ______There's just one more thing. You want one doll to spin slower and one faster. Any ideas? Try them out with your gear set. ______Draw a sketch of your design here:

GEARS AND GEAR SYSTEMS

The gears opposite are called spur gears because they mesh together. Gear ‘A’ is called the ‘driver’ because this is turned by a motor. As gear ‘A’ turns it meshes with gear ‘B’ and it begins to turn as well. Gear ‘B’ is called the ‘driven’ gear.

GEARS AND GEAR SYSTEMS

http://www.technologystudent.com/gears1/gears1.htm

Gears can be found in many machines in a workshop or factory and at home they are often an important part of mechanical devices. In a car the gears help the driver to increase and decrease speed as he/she changes the gears with the gear stick. Can you name and describe a mechanical device with gears, that you or your friends use?

The gears opposite are called spur gears because they mesh together. Gear ‘A’ is called the ‘driver’ because this is turned by a motor. As gear ‘A’ turns it meshes with gear ‘B’ and it begins to turn as well. Gear ‘B’ is called the ‘driven’ gear.

Gear ‘A’ has 30 teeth and gear ‘B’ has 20 teeth. If gear ‘A’ turns one revolution, how many times will gear ‘B’ turn? Which gear revolves the fastest?

When gear 'A' completes one revolution gear 'B' turns 1.5 revolutions (1½ times) You should have also found the gear ‘B’ revolves the fastest. A basic rule of gears is - if a large gear (gear ‘A’) turns a small gear (gear ‘B’) the speed increases. On the other hand, if a small gear turns a large gear the opposite happens and the speed decreases.

Many machines use gears. A very good example is a bicycle which has gears that make it easier to cycle, especially up hills. Bicycles normally have a large gear wheel which has a pedal attached and a selection of gear wheels of different sizes, on the back wheel. When the pedal is revolved the chain pulls round the gear wheels at the back.

Look at the gear wheel with the pedal attached and compare it in size to the gear wheels in the centre of the back wheel. What do you notice about them?

Can you name any other machines that use

gears? Most people have cycled a bicycle up a hill. The steeper the hill gets the more difficult it is to pedal and normally a cyclist will change gears to make it easier. When the cyclist changes gear, the chain moves from a small gear to a larger gear with more teeth, making it easier to push the pedals round. The more teeth the back gear has, the easier it is to cycle up hill although the bicycle moves forward more slowly. What will happen if a cyclist going up a hill changes gear from a larger to a smaller gear wheel? Will it be easier or harder to pedal? GEAR RATIO (VELOCITY RATIO) The reason bicycles are easier to cycle up a hill when the gears are changed is due to what is called Gear Ratio (velocity ratio). Gear ratio can be worked out in the form of numbers and examples are shown below. Basically, the ratio is determined by the number of teeth on each gear wheel, the chain is ignored and does no enter the equation. EXAMPLE: If the pedal gear revolves once how many times will the sprocket gear revolve?

The example above shows that every time the pedal gear revolves once the sprocket gear on the back wheel revolves twice making it easier to cycle up hill. GEAR RATIOS (VELOCITY RATIO) - QUESTIONS V. Ryan © 2003 http://www.technologystudent.com/gears1/gearat2.htm TRY THE FOLLOWING QUESTIONS :

1. If the pedal gear revolves once how many times will the sprocket gear revolve?

PULLEYS AND LIFTING - IMPORTANT FORMULAS V. Ryan © 2004 http://www.technologystudent.com/gears1/pulle12.htm When using pulleys for lifting the formulas for mechanical advantage and velocity ratio are very important. The formulas are shown below. FORMULAS RELATING TO MECHANICAL ADVANTAGE Mechanical advantage is defined as the ratio of load to effort. Pulley systems rely on this important relationship between load and effort. The formula seen below is best understood by writing it within a triangle. This helps when it is necessary to change the formula to find either; mechanical advantage or the load or the effort. In this way three formulas can be generated from the single formula inside the triangle.

FORMULAS RELATING TO VELOCITY RATIO Velocity Ratio (sometimes called movement ratio)- is defined as the ratio of the distance moved by the effort to the distance moved by the load. The formula seen below is best understood by writing it within a triangle. This helps when it is necessary to change the formula to find either; velocity ratio or the distance moved by the load or the distance moved by effort. In this way three formulas can be generated from the single formula inside the triangle.

PULLEYS 1 HYPOTHESIS If we had to lift a heavy load, pulleys can make the job easier. MATERIALS 1 board and pulley 15 weights 1 rope 1 small bucket 1 pulley 1 load 1 large bucket 1 clamp 2 hooks PROCEDURE 1. Clamp the board to your desk. 2. Hook the rope to the small bucket. 3. Put the load in the small bucket.

4. Put the rope over the top of the board. See Figure 1. 5. Tie the loose end of the rope to the large bucket. Make the rope short enough so that the large bucket is near the board. 6. GENTLY put the weights into the large bucket one at a time until the load just lifts off the ground. If you can slide a piece of paper under the edge of the small bucket, you have added enough weights. 7. Record the number of weights you needed. 8. Take the weights out of the large bucket and take the buckets off the rope. 9. Repeat this experiment two more times: first use the setup in Figure 2 and then the one in Figure 3. SETUP WEIGHTS NEEDED No pulleys

1 pulley

2 pulleys CONCLUSION How can pulleys help us? ______

PULLEYS 2 HYPOTHESIS You don't get something for nothing! Pulleys make it easier to lift heavy loads, but at a price: you can't lift the load as fast. MATERIALS 1 board and pulley 2 rulers 1 rope 1 small bucket 1 pulley 1 load 2 hooks 1 clamp PROCEDURE 1. Prepare the setup as shown in Figure 1.

2. Hold the loose end of the rope right where it comes out of the pulley. The rope should be tight, but the load should still be on the floor. 3. Hold one of the rulers so that one end is right by your hand. See Figure 2. 4. Pull the rope 30 cm to the other end of the ruler and hold it here. 5. While you hold the rope still, have your partner measure the height of the bottom and record it. 6. Repeat these steps with the 2 pulley setup that we used in the previous experiment. Be careful to pull the rope exactly 30 cm. SETUP HEIGHT OF LOAD (inches) 1 pulley

2 pulleys CONCLUSION What are two differences between using one and two pulleys?

PULLEYS AND LIFTING QUESTION

1a. What is the mechanical advantage of this pulley system?

1b. What is the velocity ratio of the system?

1c.What effort is required to lift the load?

1d. If the system moves the load 5metes upwards, how far must the effort move?

1e. With the aid of a diagram, describe how the pulley wheel at the top of the pulley system could be fixed in position, with enough strength to hold heavy weights.

How a Block and Tackle Works Brain, Marshall. "How a Block and Tackle Works." 01 April 2000. HowStuffWorks.com. 19 July 2008. If you have ever looked at the end of a crane, or if you have ever used an engine hoist or a come- along, or if you have ever looked at the rigging on a sailboat, then you have seen a block and tackle at work. A block and tackle is an arrangement of rope and pulleys that allows you to trade force for distance Imagine that you have the arrangement of a 100 pound (45.4 kilogram) weight suspended from a rope, as shown below:

In the above figure, if you are going to suspend the weight in the air then you have to apply an upward force of 100 pounds (45.4 kg) to the rope. If the rope is 100 feet (30.5 meters) long and you want to lift the weight up 100 feet (30.5 meters), you have to pull in 100 feet (30.5 meters) of rope to do it. This is simple and obvious.

Now imagine that you add a pulley to the mix, as shown below:

Does this change anything? Not really. The only thing that changes is the direction of the force you have to apply to lift the weight. You still have to apply 100 pounds (45.4 kg) of force to keep the weight suspended, and you still have to reel in 100 feet (30.5 meters) of rope in order to lift the weight 100 feet (30.5 meters).

The following figure shows the arrangement after adding a second pulley:

This arrangement actually does change things in an important way. You can see that the weight is now suspended by two pulleys rather than one. That means the weight is split equally between the two pulleys, so each one holds only half the weight, or 50 pounds (22.7 kilograms). That means that if you want to hold the weight suspended in the air, you only have to apply 50 pounds

(22.7 kg) of force (the ceiling exerts the other 50 pounds (22.7 kg) of force on the other end of the rope). If you want to lift the weight 100 feet (30.5 meters) higher, then you have to reel in twice as much rope 0- 200 feet (0 – 61 meters) of rope must be pulled in. This demonstrates a force-distance tradeoff. The force has been cut in half but the distance the rope must be pulled has doubled.

The following diagram adds a third and fourth pulley to the arrangement:

In this diagram, the pulley attached to the weight actually consists of two separate pulleys on the same shaft, as shown on the right. This arrangement cuts the force in half and doubles the distance again. To hold the weight in the air you must apply only 25 pounds (11.4 kg) of force, but to lift the weight 100 feet (30.5 meters) higher in the air you must now reel in 400 feet (122 meters) of rope.

A block and tackle can contain as many pulleys as you like, although at some point the amount of friction in the pulley shafts begins to become a significant source of resistance.

Another good example is a simple hydraulic system, as shown below:

Assume that you have two cylinders full of water with a pipe connecting the two cylinders together as shown. If you apply a force F to the left-hand plunger, it creates a pressure in the left-hand cylinder. Let's say you apply a 5 kg downward force to the left-hand cylinder. Let's also say that the radius of the left-hand cylinder is 2 cm. Therefore, the area of the left-hand piston is Pi * 2 * 2 = 12.56 cm2. If the radius of the right-hand cylinder is 4 times greater, or 8 cm, then the area of the right-hand piston is 200.96 cm2, or 16 times greater. If you push the left-hand piston down through 40 cm with a force of 5 kg, then the right-hand piston will rise 2.5 cm with a force of 80 kg. Hydraulic cylinders of all sorts take advantage of this simple force-multiplying effect every day.

You can see that a block and tackle, a lever, and a hydraulic system all do the same thing: they let you magnify a force by proportionally diminishing the distance through which the magnified force can act. It turns out that this sort of force multiplication is an extremely useful capability! Here are some of the devices that use these simple principles:

Car jack (lever or threaded gear) Can opener (gear, lever) Fingernail clippers (lever) Crowbar (lever) Automobile transmission (gears) Hammer claw (lever) Come-along (block and tackle, gear) Bottle opener (lever) Elevator (block and tackle) Car brakes (hydraulics) Hydraulic shop lift

I. MOTION COMMOTION! The Tech Museum of Innovation 201 South Market Street, San Jose, CA 95113 Phone: 408- 294-8324 www.thetech.org *http://www.thetech.org/education/downloads/dconline/motionCommotion_2003.pdf Inspired by the whimsical drawings of Rube Goldberg, students will leverage their knowledge of forces, work, simple machines and conservation of energy to design and build complex contraptions to complete a simple task. Curriculum Expectations: 1) Students will be able to identify and build Simple Machines that will work together to form a Complex Machine. 2) Students will observe and make use of the Mechanical Advantage that Simple Machines provide. 3) Students will demonstrate their knowledge of work and, forces by designing a contraption to complete a simple task. All Grades: Investigation and Experimentation: Scientific progress is made by asking meaningful questions and conducting careful investigations. As a basis for understanding structures and mechanisms and addressing the content in the other three strands, students should develop their own questions and perform investigations. Estimated Time: 1 hour . Basic Science Discussion (Simple Machines): 10 minutes . Design Challenge: . Building – 35 minutes . Sharing – 10 minutes . Clean-up – 5 minutes ADVANCED PREP AND SET-UP Design Challenge: Each team of two to three will have: . One set of plastic K’nex™ and/or 1 set plastic Tinker Toys™ . A small bell . General supplies available to everyone (from long table on side of room): Balloons, Rubber bands, Paper cups, Dowels, Wooden skewers, Film canisters, String, Tape, Drinking straws, Pipe cleaners, Cardboard/heavy paper, Paper towel rolls, Toilet paper rolls, Springs, Marbles, Ping pong balls, Clothespins, Plastic spoons, Foam pipe insulation Student research station . Mouse Trap™ board game . Frigits™ construction kit . Magnetic Gears ™ (optional) . Book: Rube Goldberg: Inventions (optional) . Book: Gizmos & Gadgets: Creating Science Contraptions That Work (& Knowing Why) Various household objects that are simple machines (with labels indicating which simple machines) . Various K’nex toy creations (optional) III. MOTION COMMOTION!: LESSON PLAN Introduction: Talk about Rube Goldberg and Heath Robinson (UK cartoonists from same era that drew similar contraptions). Show images of Rube Goldberg designs and discuss how his illustrations made simple tasks into incredibly complex, but whimsical, multi-stepped procedures. Introduce students to toys such as Frigits™, Magnetic Gears™, and the board game Mouse Trap™. Discuss the simple machines that are being utilized and the energy transfers that are occurring within the toys. Let students know that they will have an opportunity to research these toys further, to assist them in their own design process. 1. Real World Application Discussion: . Present a student with a paint can and ask Teacher Notes him/her to open it. Ask if a tool would Work: help(screw driver). A force acting on an object to move it across . Present a student with a load of books and ask a distance. Pushing, pulling, and lifting are him/her to move it across the classroom. Ask if common forms of work.

a tool would help (cart). Ask what they would Simple Machines: need to make it easier to move the load Simple tools used to make work easier. upstairs (elevator or ramp). If elevator is These include the pulley, lever and inclined offered ask what they would want to use if plane. Variations of the most basic simple there was no elevator (ramp). machines include the screw, wheel and axle, Point out that all the tools mentioned are and wedge. examples of simple machines (lever, wheel & Compound machines: axel, pulley, inclined plane) and that these tools Two or more simple machines working are provide something called a mechanical together to make work easier. advantage (MA), which makes work easier. Machine: A device that lets us do work with less effort by transferring a force. Mechanical Advantage: When a machine puts out more force than is put in, the machine is said to have mechanical advantage. The mechanical advantage can be found by dividing the force of the machine by the force you used on the machine…in other words, dividing the load or resistance by the effort. 2. Discuss Mouse Trap™ game (Research Station item): Present the game Mouse Trap™ to students and Teacher Notes: ask them to first identify all of the energy Simple Machines reduce the effort (force) transfers. Then ask students to identify all of the needed to get the job done. However, the various Simple Machines that are being utilized trade-off is that this is done by moving things (inclined planes, levers, wheel & axels). Ask a greater distance. In short, the equation students if the game utilizes elastic and balances out and in the end, the amount of gravitational potential energy (yes), if so, indicate work (force x distance) you do is exactly the where. Ask them how the series of simple same. machines conveying mechanical advantage at Lever trade-off: By changing the position of each step contribute to accomplishing an overly the fulcrum, you can gain extra power with complex task. less effort, however, you will need to cover more distance to move a load a proportionally shorter distance. Wheel and Axel trade-off: The larger the diameter of the wheel, the less effort you will need to turn it, but you will have to move the wheel a greater distance to get the same work done. Gears are used to: • Reverse the direction of rotation • Increase or decrease the speed of rotation • Move rotational motion to a different axis • Keep the rotation of two axes synchronized Design Challenge: MOTION COMMOTION! Challenge: Design and construct a “Rube Goldberg” style machine (with multiple steps) to ring a bell. Constraints: . Your machine must have at least 3 energy transfer (action-reaction) steps. . Your machine needs to include 3 simple machines (2 unique). . Your machine may not have any human energy input, except to trigger the chain of events at the beginning. . You can only use the materials supplied. You can visit the research station at any time to get ideas for your design. . Each group member must participate in the design, construction, and operation of the toy.

. Demonstration and Reflection: Teacher Notes Demonstration: Have students demonstrate their Force: contraption for the class while at their tables. If A push or pull. The force applied to a students have not completed their device ask machine is called work input or effort force. them how the device would have worked. Mechanical Energy: Reflection: Each group of students will explain Energy possessed by an object due to its their design strategy and how their device uses motion or its stored energy of position. energy, forces, and motion. Instructor should ask Mechanical energy can be either kinetic leading questions to elicit student thinking and energy (energy of motion) or potential energy understanding. (stored energy of position). Teaching Points for Mechanical Advantage Kinetic Energy: (Motion & Forces content): Energy of Motion. Includes heat, sound, and . Simple Machines make work easier by light (motion of molecules). providing a mechanical advantage (the ratio of Potential Energy: effort to resistance). Energy of position; energy that is stored and . Simple machines reduce the amount of effort held in readiness. Includes chemical energy, needed to move something, but the trade off is such as fossil fuels, electric batteries, and the that you move it a greater distance to food we eat. accomplish the same amount of work. Elastic Potential Energy: Questions to elicit student thinking & Potential energy due to tension – either understanding: stretch (rubber bands, etc.) or compression . Did you continue to work on your original (springs, etc.). design or try something new? Gravitational Potential Energy: Which simple machines did you incorporate into Potential energy stored in an object as a your design? result of its vertical position (i.e., height). . What mechanical advantage do they provide to the whole machine? . How does your toy transform potential energy (elastic or gravitational) to kinetic energy? . Did you do any research to inform your design? How did it help you? . How could you simplify this overly complex task? How might you make it more complex given more time and materials? . If you had more time what would you add, change, or do differently? Clean up: Reduce! Re-use! Recycle! Only throw away items that cannot be re-used. All items should be returned to the appropriate place. Pre- and post activities: Post-activity: Have students research Rube Goldberg and then draw a cartoon sketch of their proposed contraption. (This is a great opportunity for budding cartoonists to shine.) Have students try to build the designs that they created (improvising when necessary). Post-activity: Hold a Rube Goldberg Machine contest for the class, school or district (using whatever supplies are available to the students). Have them market their designs (create packaging, advertisements, commercials, etc). See the official website: http://www.rubegoldberg. com Extension: add a height constraint to the challenge: i.e. students contraptions should attain a vertical height of 10 cm (just an example – height can be determined by teacher.

PULLEYS AND LIFTING ANSWER SHEET

1a. What is the mechanical advantage of this pulley system?

1b. What is the velocity ratio of the system ?

1c.What effort is required to lift the load ?

1d. If the system moves the load 5metes upwards, how far must the effort move?

1e. With the aid of a diagram, describe how the pulley wheel at the top of the pulley system could be fixed in position, with enough strength to hold heavy weights. Steel bolts could be used to hold the weight of the pulley system. One advantage of using bolts is that they can be removed easily so that the pulley system can be dismantled

MECHANISMS LESSON STARTER http://www.technologystudent.com/cams/camdex.htm V. Ryan © 2005 A number of mechanisms are drawn below. Write the correct name beneath each one. CHAIN AND SPROCKET SYSTEM - LEVERS - LINKAGES - SPUR GEARS - PULLEY - SYSTEM - DROP CAM - SCREW THREAD - RACK AND PINION - SPRING

G LOSSARY & CONCEPTS: Physics Terms . Conservation of Energy: Energy cannot be created or destroyed; it may be transformed from one form into another, or transferred from one place to another, but the total amount of energy never changes. Compound machines: Two or more simple machines working together to make work easier. . Elastic Potential Energy: Potential energy due to tension – either stretch (rubber bands, etc.) or compress (springs, etc.). . Energy: “Nature’s way of keeping score.” Measured in joules Appears in many forms, most of which are ultimately derived from the sun or from radioactivity. . Force: A push or pull. The force applied to a machine is called work input or effort force. . Fulcrum: a lever’s pivot point. . Gravitational Potential Energy: Potential energy due to elevated position. Gravitation potential energy = weight x height. Note this only depends on vertical displacement and not the path taken to get it there. This value is always relative to some reference level. . Inclined plane: A sloped surface that does work by trading force for distance. This includes ramps, wedges, screws, and scissors/cutters. . Kinetic Energy (KE): Energy of motion. KE= ½ mass x velocity2 = ½mv2 Note that small changes in speed can result in large changes of KE (it is speed squared!). Net force x distance = KE. This includes heat, sound, and light (motion of molecules). KE is a scalar quantity; it cannot be cancelled. . Lever: A bar resting on and tending to rotate about a fixed point when force is applied. The lever type is determined by the order of load/fulcrum/force as described below: First class lever: load-fulcrum-force; force & load move in the opposite direction; seesaw. Trades force for distance. Second class lever: force-load-fulcrum; force and load move in same direction; wrenches, wheelbarrows. Third class lever: fulcrum-force-load; force & load move in same direction, but force cannot travel farther than load (no positive mechanical advantage); arms, legs, fishing poles, cranes, and backhoes. Useful for reaching; always sacrifices force for distance. Cantilever: A lever with one end supported and the other end free. . Machine: a tool used to make work easier. Simple machines are simple tools used to make work easier. Compound machines have two or more simple machines working together to make work easier. . Machine (more complex definition): A device for multiplying forces or simply changing the direction of forces. Note that machines cannot multiply or create work or energy – that goes against the law of conservation of energy! Any machine that multiplies force does so at the expense of distance; any machine that multiplies distance does so at the expense of force. . Mechanical Advantage: The number of times a machine multiplies the effort force (The mechanical advantage can be found by dividing the force of the machine by the force you used on the machine). . Mechanical Energy: Energy possessed by an object due to its motion or its stored energy of position. Mechanical energy can be either kinetic energy (energy of motion) or potential energy (stored energy of position). . Potential Energy (PE): Energy of position; energy that is stored and held in readiness. Includes chemical energy, such as fossil fuels, electric batteries, and the food we eat. . Simple Machines: Simple tools used to make work easier. These include the pulley, lever and inclined plane. Variations of the most basic simple machines include the screw, wheel and axle, and wedge. . Work: A force acting on an object to move it across a distance. Pushing, pulling, and lifting are common forms of work. __ Wheel and Axle: Something round that turns around or with a rod. Does work by trading force for distance. Circumference of wheel is greater than circumference of axle – apply smaller force over large wheel distance to move object. Wheel & axle may or may not turn independently.

- Gears: Toothed wheels. Mechanical advantage occurs when the two gears are not the same size. If a little gear turns a big gear, the big one turns slower than the small gear, etc. - Pulleys: Grooved wheel (to hold rope). - Fixed pulley: is attached to an anchor. It does not change the amount of force required to perform a task, it only allows you to change the direction in which the force is applied. __Moveable pulley: is attached directly to the load and lifts with it. - Block and tackle: A compound machine made of fixed and movable pulleys. Weight is evenly divided between the number of lines that support it. Block=pulleys; Tackle=lines/ropes. - Hinges: Think of the wheel as the frame attached to the door and the jamb, and the axle is the pin that holds two frames together.

RESOURCES __ Conceptual Physics for Parents and Teachers: Mechanics by Paul Hewitt. Focus Publishing/ R. Pullins Company, Newburyport, MA. 1998. __ Exploring Energy with Toys by Beverley A. P. Taylor. Terrific Science Press, Middletown, OH, 1998. __ Gizmos & Gadgets: Creating Science Contraptions that Work by Jill Frankel Hauser. Williamson Publishing, charlotte, Vermont. 1999. __ The Inventa Book of Mechanisms by Dave Catlin. Valiant Technology Ltd., London, England, U.K., 1995. __ Rube Goldberg Inventions by Maynard Frank Wolfe. Simon & Schuster, New York, New York. 2000. __ Simple Machines by Fran Whittle and Sarah Lawrence. Raintree Steck- Vaughn Publishers, Austin TX, 1998. __ Simple Machines Made Simple by Ralph St. Andre. Teacher Ideas Press, Englewood, CO, 1993.

WEBSITES SITES FOR STUDENTS THAT RELATE TO CENTERS The Physics Classroom lessons website: http://www.glenbrook.k12.il.us/gbssci/phys/Class/energy/energtoc.html Describes work and has a self test for students to assess their understanding of the concept of work http://home.earthlink.net/~dmocarski/chapters/chapter5/ch5page.htm website describing the principles of work etc for grade9s http://education.jlab.org/sciencecrossword/simple_machines_01.html online crossword for simple machines http://www.forgefx.com/casestudies/prenticehall/ph/catapult/catapult.htm a virtual site to launch a catapult http://www.thetech.org/exhibits_events/online/robots/overview/ gives a description of a robotic arm with good visuals BUILDING AUTOMATA FUN SITES FOR EVERYONE http://web.mac.com/plowndes/Contemporary_Automata/My_Beautiful_Hair.html fun use of cams this video is fun and the toy movements are pretty cool when you think about the engineering http://www.mechanicalmonkey.co.uk/Dragon.html commercial site with videos to show movements http://www.flying-pig.co.uk/ has many mechanical toys and demonstrates the mechanisms http://automata.co.uk/ has many mechanical toys and demonstrates the mechanisms http://en.wikipedia.org/wiki/Mechanical_toy info on theory of mechanical toys SITES FOR TEACHERS http://www.dogpile.com/dogpile_200/ws/results/Web/simple+machine/1/417/TopNavigation/Relev ance/iq=true/zoom=off/_iceUrlFlag=7?_IceUrl=true list of useful websites to develop plans for unit

53 Grade 8: Structures and Mechanisms http://www.shambles.net/pages/learning/DandT_S/Y9Mtoys/ list of potential sites good for navigating to different places NOVA web connections Nova has tons of great information on Structures and Mechanisms. You could spend a day or two just surfing their site. There are activities, videos, worksheets and more! http://www.pbs.org/wgbh/nova/teachers/activities/27po_sle2phar.html- connection to ancient civilization. Great for Gr 5 http://www.pbs.org/wgbh/nova/teachers/activities/27ms_sle2treb.html connection to medieval times Gr 4 *http://www.pbs.org/wgbh/nova/teachers/activities/2405_sle1obel.html used for levers section. Part of a bigger lesson on Egyptians building obelisks http://www.sciencenetlinks.com/pdfs/simple_actsheet.pdf worksheet for simple machines *http://www.thetech.org/education/downloads/dconline/motionCommotion_2003.pdf has lesson plan for centers *http://www.thetech.org/education/downloads/dconline/motionCommotion_2003.pdf has lesson plan for centers http://www.thetech.org/education/programs/classroom/ a pile of downloadable lessons that relate to structures and mechanisms, one that relates to ancient civilizations etc very cool http://www.thetech.org/education/downloads/dconline/treeHouseEscape.pdf possible lesson plans for a tree house and simple machines http://www.thetech.org/exhibits/online/robotics/ questions about robotics, ethics and their role *http://www.technologystudent.com/gears1/geardex1.htm used for stations gears and pulleys http://www.design-technology.info/systems/default.htm http://www.howstuffworks.com/pulley.htm?printable=1 how stuff works used it for background info http://www.sciencenetlinks.com/tools.cfm?DocID=66&Grade=3-5 *http://www.galaxy.net/~k12/machines/index.shtml USED THIS FOR BASIC EXPERIMENTS *http://www.technologystudent.com/index.htm has a lot on simple machines and on other *http://www.galaxy.net/~k12/machines/index.shtml used extensively *http://www.mos.org/sln/Leonardo/InventorsToolbox.html used in glossary

* Denotes sites that were used to source activities for centers in this lesson plan

GRADE 8 STRUCTURES AND MECHANISMS ACTIVITY #6: A DESIGN CHALLENGE CULMINATING UNIT TASK BUILDING A MECHANICAL DEVICE TO MOVE AN ELEPHANT

The Task: The students design and build a mechanical arm or a device that has to move an elephant that has injured itself, fell down and cannot get back onto a truck to be brought to an animal hospital for treatment. Once each student has designed and built an “elephant-lifting” machine, he/she will write an owner’s manual for the device. In this owner’s manual, the student will communicate what he/she has learned about structures, systems, and simple machines.

Curriculum Expectation: 2.1 2.2 2.3 2.4 2.5 2.6 2.7 3.5 3.6 Preparation Time: approx. 1 hour Lesson Duration: 5 x 70 min. periods for student research, planning and construction of device 1 x 70 min. presentation Purpose: To allow students to make connections between current unit and STSE implications Materials: Consumables . Recycled materials from around house . Vocabulary list . Ziploc bags (one per student) . sand . Photocopied rubrics Non-consumables . c-clamps . gears . glue guns . hammers . hand drills with bits . hand saws . 100g mass . 500g mass . Pliers . Safety glasses . Screwdrivers . Portable vices . Steel rulers . Tape measures . Work gloves . Various adhesives (glue gun, tape, spring, paper clips, screws, nails, etc.) . Cutters Method: Teacher Preparation:  prepares a variety of recycled materials i.e. foam, egg cartons, various containers, sewing spools, etc. from around the home in a box to allow students with a building opportunity even though they may not have the ability to bring items into the classroom for building  obtains several Owner’s Manuals as exemplars  prepares a vocabulary list of words relating to unit  prepares a variety of hand and power tools for student use

Student Preparation:  collects a variety of used materials from around the house  student thinks of tools to use for building

 student brings materials and tools to class  student draws on prior learning in the class about structures to be able to complete this culminating task

Delivery method:  At the start of a unit, teacher gives the following scenario to the class and explains the expectations and procedure for the building assignment o Scenario:

The Metro Toronto Zoo houses a two ton elephant that has injured itself. The elephant is unable to get up or move. The students design and build a mechanical arm or a device that has to move an elephant onto a truck so that the elephant can be brought to the animal hospital

o Criteria:  Work independently  Design is clear and to scale  Device contains the use of at least three simple machines to form a system  Device is made of recycled materials from around the home  Students bring their own materials and tools to class  Students research their ideas throughout the unit  Students complete the building challenge in class in (TENTATIVELY 5 class) periods  Students collect any work samples or research into the scrapbook throughout activity  Device is able to carry and move a 500g bag of sand up 10cm and back down 5cm, as well as rotate to move sand bag onto truck platform  Students present the machine using the attached vocabulary and demonstrating how much weight their machine can move and how it operates

 Scale Diagram: o Students draw a rough plan for their machine in their design booklet o Students create a scaled diagram of the device using proper drafting skills i.e. use of rulers, etc. showing two views i.e. side view and front view o Students label the diagram with accurate and scaled, measurements and dimensions  Building Process: o Students will build a device that contains at least three simple machines to carry the elephant from one place to another. o The students are allowed to research building strategies for one period in the library and one period on the internet. o Students build their device in class using the tools and materials provided.  Testing & Revision of model: o Students test their model for the ability to carry the 500g sand bag. o Students revise and modify their plan, design and model if tests prove inconclusive or inefficient. o Students record their modifications and testing process in the design booklet o Students calculate work and mechanical advantage of their device.

MA = Load Force (FL) = Effort Arm Effort Force (FE) Load Arm

Work = Force x distance W = F x d

 Reflection: o Students discuss the strengths and weaknesses of your machine in the booklet.

 Summative Writing Task: o Teacher shows class various owner’s manuals to demonstrate different styles o Students create an owner’s manual for their device to communicate the information learned about structures, systems, and simple machines

Assessment:  Qualitative - Checklist for completion of design booklet  Quantitative - A levelled rubric for checking understanding of simple machines, how systems operate and the design and inquiry process  Quantitative – a levelled rubric to assess the visual & oral (presentation) and written components of the presentation

Accommodations:

For students who need a higher challenge, they can incorporate the use of a pneumatic and/or hydraulic system in their machine. As an STSE and language-rich task, students can create an advertisement to sell their device to the public.

DESIGN AND INQUIRY RUBRIC FOR STRUCTURES AND MECHANISMS CULMINATING PREFORMANCE TASK

Assessment for Rich Performance Task: A Mechanical Device for Moving an Elephant from One Place to Another

Criteria Level 1 Level 2 Level 3 Level 4 Score

Model Design - applies few of the required skills - applies some of the required - applies most of the required skills - applies all (or almost all) of the and Building and strategies; skills and strategies; and strategies; required skills and strategies; Initiating and Has difficulty understanding design Has emergent understanding of Has good understanding of design Has excellent understanding of /16 K/U Planning task or adhering to parameters set design task and adheres to a few task and adheres to most design task and adheres to all out in design challenge parameters set out in design parameters set out in design parameters set out in design challenge challenge challenge Understanding No drawings submitted Drawings submitted but very Clear drawings submitted, many Drawings of exceptional clarity the need rough, few details included details are provided (top, side and submitted: include high quality Materials not considered Materials considered but many front view) details (Scale, top, side and front Making a plan inappropriate choices Materials considered with many view, in situ planning of performing appropriate choices and task) sometimes demonstrates intended Materials carefully considered and needs and application rationalized; materials clearly K/U reflect intended application and performance needs Performing and Does not follow any plan to Follows most identified plans to Follows identified plans to Follows identified plans to /12 A Recording construct model construct model construct model, and makes some construct model and justifies Data are not recorded in booklet or Data recorded in booklet are of modifications modifications is irrelevant limited relevance, are limited in Data recorded in booklet are Data recorded in booklet are /4 C Carrying out the Display of information is scope, and/or contain major relevant and sufficient in scope relevant and may be extensive in plan/keeping a disorganized, not precise, accurate inaccuracies and detail, but not extensive scope and detail design booklet or complete Display of information is somewhat Display of information is Display of information is organized, Units, where appropriate, are not organized, and somewhat precise, organized and mostly precise, precise, accurate and complete indicated accurate and complete accurate and complete All units, where appropriate, are Units, where appropriate, are often Most units, where appropriate, are included A and C incorrect or are not included included Interpreting, Is unable to analyze if device Is occasionally able to analyze if device Is able to analyze if device meets Is clearly able to analyze whether /12 T/I Analysing, meets design criteria or uses meets design criteria and occasionally design criteria and usually uses device meets design criteria. uses criteria that are relevant criteria that are relevant Calculating criteria that are irrelevant Relevant criteria are identified, Criteria are not analysed or Relevant criteria are partly identified Relevant criteria are identified and analysed and explained (Work & and explained, without analysis explained with partial analysis explained Is able to propose some modifications Is able to propose and implement Mechanical Is unable to propose or implement Is able to propose and implement modifications to design that clearly to design; unable to successfully some modifications to design; Advantage), modifications to design to improve implement proposed modifications to improve task performance proposed modifications have limited task performance improve task performance Evaluating and effectiveness to improve task Device addresses all criteria and Device does not address criteria Device addresses a few criteria or/ performs the original task with Revising and performs the original task with performance or perform the original task; Device addresses many criteria high level of efficiency and limited effectiveness effectiveness Looking back or/ and performs the original task Performs calculations of work & with effectiveness Omits calculations of work & mechanical advantage but does so Performs calculations of work & mechanical advantage or with limited effectiveness Performs calculations of work & mechanical advantage with a T/I and A performs incorrectly mechanical advantage with high level of effectiveness /4 A effectiveness Grade 8: Structures and Mechanisms Skills in the - uses tools, equipment, and uses tools, equipment, and uses tools, equipment, and uses tools, equipment, and safe use of materials correctly only with materials correctly with some materials correctly with only materials correctly with little or no tools, assistance; assistance; occasional assistance; assistance; equipment, and materials Choosing and Needs assistance to choose and Needs some assistance to choose Chooses and uses appropriate Chooses and uses appropriate /4 T/I using tools, accurately use appropriate tools, and accurately use appropriate tools, equipment and materials tools, technologies and materials equipment and equipment and materials to tools, equipment and materials to accurately and with only minor accurately and proficiently to construct and test model efficiently construct and test model efficiently errors to construct and test model construct and test model efficiently materials and effectively and effectively efficiently and effectively and effectively

T/I Safety Does not follow safety Follows some safety Follows most safety considerations Follows all safety considerations /4 K/U Procedures considerations without constant considerations but needs some but needs occasional supervision without supervision and follows supervision and needs continuous supervision and needs occasional and needs few reminders to follow appropriate and safe procedures assistance to follow appropriate reminders to follow appropriate appropriate and safe procedures K/U and safe procedures and safe procedures Effective - rarely uses effective - sometimes uses effective - often uses effective - consistently uses effective Communication communication skills in oral, visual communication skills in oral, visual communication skills in oral, visual communication skills in oral, visual Skills and written presentations and written presentations and written presentations and written presentations

Presentation Is unclear in explaining the Somewhat effectively explains the Effectively explains the operation Effectively explains the operation /4 C operation of their device. Rarely operation of their device. of their device. Frequently uses of their device. Consistently uses (Oral & Visual) uses correct presentation skills Sometimes uses correct correct presentation skills (clear, correct presentation skills (clear, (clear, fluent, strong voice & presentation skills (clear, fluent, fluent, strong voice & posture, fluent, strong voice & posture, posture, organized, engages strong voice & posture, organized, organized, engages audience) organized, engages audience) C (**see notes audience) engages audience) below) Owner’s Owner’s Manual is disorganized in Some of the Owner’s Manual is Most of the Owner’s Manual is All of the Owner’s Manual is /10 C Manual appropriate sections (i.e. title page, organized into appropriate sections organized into appropriate sections organized into appropriate sections table of contents, explanation of (i.e. title page, table of contents, (i.e. title page, table of contents, (i.e. title page, table of contents, (Written) parts, diagrams, operation of explanation of parts, diagrams, explanation of parts, diagrams, explanation of parts, diagrams, device). It contains a minimal operation of device). It is at least 3 operation of device). It is at least 4 operation of device). It is at least 5 amount of work in the write-up. pages in length. Some of the pages in length. Most of the pages in length. The whole manual The whole manual is unclear and manual is clear to read and manual is clear to read and is clear to read and interpret. hard to read and interpret. All interpret. Diagrams are somewhat interpret. Most diagrams are Diagrams are clearly drawn, diagrams are unclear or not clearly drawn, labelled and are to clearly drawn, labelled and are to labelled and are to scale. ) Has C present. Has no disclaimers for scale. ) Has attempted to include scale. ) Has at least one clear disclaimers for limits of technology. limits of technology. disclaimers for limits of technology. disclaimer for limits of technology. **The presentation of the device to the class will be graded solely with respect to the student’s oral and visual communication skills. In other words, for this part of the assessment, it doesn’t matter whether or not the device performs the original task. If the student shows good communication skills, is able to discuss why the device did or did not operate as expected, and suggests possible revisions to the design (if necessary), the student should still do well in this area of the assessment. This approach will also be taken to the assessment of the written owner’s manual. Names: ______

Making the Plan 1. Restate the need.

2. Exploring ideas. (Briefly describe and sketch possible solutions in the spaces below).

1 Names: ______

3. Select your preferred solution and explain why you made this choice.

4. Label a drawing of your design on a sheet of graph paper which you will hand in with the rest of this booklet. Note: Your drawing should be to scale and should include top, side and front views of your machine.

5. Outline the design process steps followed in constructing, testing, and revising your solution.

2 Names: ______

Executing/Evaluating the Plan Get a 500 g bag of sand (i.e., “the elephant”) and try out your machine. Be sure to calculate work (i.e., w = f x d ) and the mechanical advantage (i.e., MA = force needed without simple machine/force needed with simple machine = load/effort) of your machine, making sure to explain your work using numbers, words, and pictures.

3 Names: ______

Reflection 1. Was your machine successful in lifting “the elephant?” Discuss the strengths and weaknesses of your machine.

4 Names: ______

2. Describe how you might improve your machine if you were to build it again in the future.

Note -- This booklet was closely modeled after worksheets shown in: Ministry of Education and Training. (2002). The Ontario curriculum – Exemplars Grades 7 and 8: Science and technology. Toronto: Queen’s Printer for Ontario.

Michaela Timciska, Diane Williams & Gigi Shanks Grade 8: UNDERSTANDING STRUCTURES AND MECHANISMS: SYSTEMS IN ACTION

ACTIVITY #5: TOWN HALL FORUM Curriculum Expectations: 1.1-assess the social, economic and environmental impacts of automating systems 1.2-assess the impact on individuals, society, and the environment of alternative ways of meeting needs that are currently met by existing systems, taking different points of view into consideration 3.9-identify social factors that influence the evolution of a system Preparation Time: approx. 1 hour Lesson Duration: 1 x 70 min. preliminary lesson 2 x 70 min. periods for student research and planning of arguments 2 x 70 practice and final Town Hall Forums Purpose: To allow students to make connections between Systems in Action and STSE expectations Materials: Library access Computer lab access Scenario cards Description of roles Method: Teacher Preparation: Create sheets with descriptions of roles Create scenario cards Describe and explain “stakeholder” Book the library and computer lab (approximately 1 hour for each) Student Preparation: Throughout the unit, create a scrapbook of newspaper and magazines articles to develop background understanding of relevant issues that pertain to scenario prior to Town Hall Forum Give one library research period Give one internet research period

Delivery Method: Day 1: Introduction Explain the Town Hall Forum procedure to the class (example: stating arguments, how to refute) and set expectation for the Town Hall Forum including acceptable behaviour during the forum. Give the following scenario to the class:

A large pulp and paper mill that provides most of the employment in a small Northern community is threatening to close. Company executives claim that the factory is no longer profitable because of antiquated equipment and processing which can be done more cost effectively off shore. A group of engineers at the mill believe the mill can be updated using environmentally responsible technologies by taking advantage of grants and become profitable once more. A multinational company has come in with a rescue deal that would keep the factory open by updating and replacing equipment with new assembly line processes and robotics. The multinational has made no guarantees that there will be no job losses. As part of the rescue plan, the multinational does not want to undergo a full environmental assessment however the multinational’s practices have been criticized abroad. The local environment has been negatively affected by the current mill and there are several aquatic species at risk that are essential in the food chain. About half of the employees at the mill have lived their entire lives in the community, are aging and have limited employment opportunities. About a third of the employees are recent graduates with young families and have relocated to the community to work. Some employees are immigrants to Canada who have teenage families but were not able to find employment in urban centers despite having excellent qualifications.

Student Task (Role Summary) Your task is to explain the citizen’s perspective and to propose a solution that you believe is satisfactory from that citizen’s perspective. You will have about 2-3 minutes to present your position. You must explain your reasoning and support your position with evidence from the scenario and from real life examples, including evidence from your scrapbook and any interviews you conducted. You will submit a 2-page written summary, with references, prior to the Town Hall Forum. This summary will be assessed and returned to you before the Town Hall Forum.

Assign roles to each student. Some roles are designed to be more in favour of automation while others are designed to be less in favour of automation. (See Table 1 for Roles)

Table 1: Suggested roles for Town Hall Forum DOCTOR TOWN MECHANIC LOCAL BAND BANK TELLER AN ELDERLY PLAYER PERSON LARGE-SCALE YOUNG MOTHER FACTORY MINISTRY OF TAXI DRIVER FARMER WITH CHILDREN ENGINEER NATURAL RESOURCES WORKER WAITRESS ENVIRONMENTALIST FACTORY CONSTRUCTION HIGH SCHOOL WORKER WORKER STUDENT TEACHER POLICE OFFICER FIRE FIGHTER ICE-CREAM TOWN MAYOR STORE OWNER SEASONAL SCIENTIST HUNTER SOCCER LEAGUE SEASONAL RESIDENT OWNER RESIDENT (boater) (Cottage Owner) LOCAL JUDGE TRUCK DRIVER RADIO SOCIAL WORKER VETERINARIAN STATION OWNER ORGANIC TOURIST STORE CLERK POLITICIAN AN AUTHOR FARMER

Day 1 (continued) Model the different perspectives of a citizen (i.e. Doctor) regarding a proposal to construct a 4-lane highway through his small community. (Note: A Doctor is one role that could represent multiple perspectives) Pros Travelling to and from community would be more convenient and faster and would encourage growth of community Doctor approves of the construction of a highway through town because it would bring in more employment which would increase the size of his/her practice If families settle in the town because of new employment opportunities, there could be an increase in the number of children and sizes of families Cons Doctor may oppose construction because the employment created during construction would be dangerous and incidence of injuries to construction workers would be high; subsequent traffic-related accidents would increase Import of new infections and diseases with new residents Destruction of clean environment due to increased pollution; environment will be less healthy for the citizens living in, and around, town Population may increase but only one doctor available to care for patients Day 2 & 3: Research & Preparation Students’ research scenario from the perspective of their assigned role: These two classes take place in the library and/or computer lab. As a homework extension, students are encouraged to interview people who have some knowledge, or who may be able to contribute to students’ understanding of the student’s assigned role.

Students continually add articles/entries into their scrapbooks. This may include newspaper, magazine, journal articles, websites, book bibliographies and other referenced sources.

Day 4: Modelled Town Hall Forum Give the Scenario for this practice forum:

“A farmer wants to sell his farm to a manufacturer who will open up an automobile factory.”

Teacher Tasks: The teacher will model public speaking skills and assess students anecdotally to ensure the students have acquired the necessary skills of public speaking (see: Assessment Checklist for Practice Town Hall) and analysing an issue. To ensure that all class members participate, a two-minute time limit will be enforced. A time keeper will be assigned and will indicate by using cards amount of time remaining (e.g. 2 minutes, 1 minute, 30 seconds). When time has elapsed teacher will ask speaker to sit and call on next student. A clock will be visibly posted.

Assessment Checklist for Practice Town Hall This checklist is intended to provide you with initial feedback concerning your participation in a Town Hall discussion. Please use this information to consider how you might improve your skills prior to the Town Hall discussion of the scenario with the pulp and paper mill.

Skill or Ability Seen? Comments

Did you stick to the topic being discussed? Did you use many appropriate facts from your research to support your position? Were your arguments clear and convincing? Did you work effectively as a member of a team (where applicable)? Did you show appropriate body posture (e.g., oriented toward speakers or listeners, not slouching, head up, etc.)? Were the volume and tone of your voice appropriate for a Town Hall discussion? Did you make eye contact with other class members participating in the discussion? Did you act respectfully towards others during the Town Hall discussion? Did you actively listen when others were talking? Did you respond thoughtfully to comments made by other participants?

Student Tasks: Your task is to explain, from the perspective of the citizen’s role you have previously been assigned, that citizen’s perspective to the scenario and to propose a solution that you believe is satisfactory to that citizen. You must explain your reasoning and support your position with evidence from the scenario and from real life examples.

Day 5: The Town Hall Forum and Assessment Conduct the Town Hall Forum with the class. Students have their research scrapbooks and their role summaries to refer to as needed. Assess the debate that was researched during Days 2 and 3 using the Town Hall Rubric (below)

The teacher is the mayor of the town and facilitates the Town Hall Forum. Teacher specifies time allotted to students/turn to ensure all class members participate. To ensure that all class members participate, a two-minute time limit will be enforced. A time keeper will be assigned and will indicate by using cards amount of time remaining (e.g. 2 minutes, 1 minute, 30 seconds). When time has elapsed teacher will ask speaker to sit and call on next student. A clock will be visibly posted.

Assessment:  A levelled rubric for assessing the scrapbook using Knowledge & Understanding; Thinking & Investigation; Application and Communication  A levelled rubric for checking understanding of debate procedures and STSE issues.

66 Grade 8: Structures and Mechanisms TOWN HALL RUBRIC

1 2 3 4 Category The Park Path The Local Street Yonge Street The 401 Highway Score Addresses Issues Rarely address topic Sometimes addresses topic Usually addresses topic Always addresses topic Does not use appropriate Uses few appropriate facts Uses some appropriate facts Uses many appropriate Support with facts that support their from internet and library from internet and library facts from internet and Researched Facts position research that support their research that support their library research that position position support their position Arguments are never clear Arguments are rarely clear Arguments are sometimes clear Arguments are clear and and convincing; and convincing; and convincing; convincing; Does not introduce position Introduces topic with Grabs attention with opening Electrifies audience with Persuasiveness with opening statement; opening statement; Brings statement; Brings closure to their opening statement; Closure Brings no closure to their some closure to their position position convinces audience position Exudes limited passion; Exudes some passion; Exudes a lot of passion; Mostly Consistently exudes Rarely uses appropriate Sometimes uses appropriate uses appropriate skills such as passion; Always uses Discussion Skills skills such as body skills such as body language, body language, volume and tone appropriate skills such as language, volume and tone volume and tone of voice, of voice, eye contact body language, volume and of voice, eye contact eye contact tone of voice, eye contact Rarely uses respectful Sometimes uses respectful Usually uses respectful Always uses respectful behaviour -attentive behaviour -attentive behaviour -attentive listening, behaviour -attentive listening, courteous listening, courteous courteous responses, listening, courteous responses, thoughtfully responses, thoughtfully thoughtfully considers others’ responses, thoughtfully Social Skills considers others’ points of considers others’ points of points of view; Usually considers others’ points of view; Needed many view; Inconsistently maintains focus and remains in view; Always maintains reminders to maintain focus maintains focus and remains their seat throughout forum with focus and remains in their and remain in their seat in their seat throughout occasional reminders seat throughout forum throughout forum forum with several reminders without reminders Teamwork Neither team member One member speaks 100% of One member speaks 75% of the Used team member (where speaks the allotted time allotted time effectively; Equal sharing applicable) of speaking

67 Grade 8: Structures and Mechanisms TOTAL:

Accommodations: Roles would be assigned based on student need. For example, a gifted student would be assigned a role, such as the doctor, for which there could be multiple perspectives. ELL students or students with IEPs could be paired with stronger students to provide support. Students who frequently struggle with written tasks but who excel at oral expression would be given the opportunity to shine. Also, laminated  vocabulary folders with pictures and definitions of key vocabulary would be available for any student who required additional accommodations or English support. The criteria in the rubric for Teamwork only apply to students needing the support of a classmate.