7Th Grade Life Science: Activity Outline s1

Mystery Box (Scientific Inquiry) 2009

Purpose/Objectives:

You have been given a sealed box that contains three objects. You have also been given an identical but empty box and a tray with an assortment of objects that may have been used to fill the mystery box. Using these objects and the scientific method, you will work with your lab partners to try to determine the contents of your mystery box without opening it.

By the end of this exercise, you should be able to:

 Explain the scientific investigation method and apply it to examples.  Identify and describe questions that can be answered scientifically.  Explain what distinguishes a good scientific hypothesis.  Define, give examples of, and identify dependent and independent variables.

Background:

Whether you realize it or not, you use the process or method of scientific investigation to learn about yourself and the world around you. Scientists use this method of investigation to construct new knowledge as well. Usually the scientific process begins with a problem or question about an observation. Only questions that can be answered by making observations and gathering evidence can be solved using scientific investigation.

Once a question is identified, a testable explanation or hypothesis must be proposed. The scientific process requires that we test our hypotheses either experimentally or by further observation. Since a broad generalization is very difficult to test, one way to test a hypothesis is to make a specific prediction based on the general hypothesis.

Testing a hypothesis with scientific investigation allows us to gather evidence, or data, that will either support or contradict the hypothesis. To ensure that the test is reliable, a good scientific experiment has several important elements, including: one independent (manipulated) variable, one dependent (responding) variable, standardized variables, controls, and replication.

Vocabulary: 1 Minority Science Programs – School of Biological Sciences – University of California, Irvine Mystery Box (Scientific Inquiry) 2009

Scientific inquiry Independent variable Observation Dependent variable Hypothesis Control Prediction Replication Variable Data

Materials:

Per Group:  1 sealed box containing 3 items  1 empty box  1 tray with possible content items

Possible Items:

 Cotton balls, paper clips, buttons, binder clips, erasers, glass slides, plastic beakers  Scales or balances for further investigation

Methods/Procedure:

Use the following guidelines to direct your investigation. Record your observations and answers to the following questions in your lab write-up.

1. Make observations. Do not open the box, but use any other methods at hand to investigate it (Hint: Think about what “instruments” you have available).

2. When you think you have an idea of what items might be in your mystery box, make an initial hypothesis and record it in your lab write-up. This hypothesis should be simple and testable.

a. What were the observations that led you to make your hypothesis? ______

b. What other methods or materials might be useful to you for making additional observations about the contents of your container? ______

2 Minority Science Programs – School of Biological Sciences – University of California, Irvine Mystery Box (Scientific Inquiry) 2009

3. Discuss your hypothesis and the methods you would like to use with your lab instructor and classmates. After the discussion, the instructor will offer you some additional methods for investigating the contents of your mystery box.

4. Using some of the additional methods and/or materials, make a prediction based on your hypothesis and record it in your lab write-up. 5. Test your hypothesis/prediction and record further observations. a. Do your new observations agree with your initial hypothesis about the contents of the box? ______b. What new information leads you to conclude that your first hypothesis was correct or to revise your initial hypothesis? ______c. Write a new hypothesis in your lab write-up, next to your original hypothesis.

6. When the entire class is finished making their second hypotheses, your instructor will have each group write its hypothesis on the board. Then your instructor will reveal the contents of each mystery box. Please do not open your container.

7. Discuss and answer the following questions with your classmates after everyone has written their box contents on the board.

8. Review the process of scientific inquiry by creating a flow-chart of the procedure you used to solve your mystery box.

Methods/Procedure Flow-Chart:

Name: ______Period: ___

Questions:

1. Complete the table of experimental design elements on the lab write-up.

2. Which of the following hypotheses are testable by scientific inquiry? Explain your answers. (9 points) a. Typed lab reports receive better grades than handwritten papers do. Testable? Yes No

______

______b. Cats purr when they are happy. Testable? Yes No

______

______c. Vitamin C prevents sore throats. Testable? Yes No

______

3. For each of the following examples identify the independent and dependent variables. (10 points)

a. Running rates of lizards are measured at three different temperatures. Independent: ______

Dependent: ______

b. Corn plant height is measured for plants with and without added nitrogen. Independent: ______

Dependent: ______

c. Bean plant seed production is measured with various frequencies of insecticide spraying. Independent: ______

Dependent: ______

d. Penguins from a single clutch are split between two rooms in the Sea World penguin house. In one room the temperature is 10˚C, in the other it is 5˚C. Their weights are measured at the end of one year. Independent: ______

Dependent: ______

e. Dogs are given different foods and their blood glucose level is measured after 1 hour. Independent: ______

Dependent: ______

6 Minority Science Programs – School of Biological Sciences – University of California, Irvine