2. Designing an Experiment O-H-E-C-C

3. Determining a Purpose Do research Examine results of a previous experiment Observe the world around you

4. Experiment An organized procedure to study something under controlled conditions.

5. Purpose Write the purpose of your experiment as a question or problem that you want to investigate Write down research questions and begin searching for information that will help you design an experiment. Consult the library, internet, and other people

6. Example What is Gary’s purpose of this experiment? Gary observed that he seems to be able to concentrate more and seems smarter after he eats Super Snail Snacks. He also noticed that his friend Barry also had experienced the same effects. Gary and Barry did some research to learn more about their observations. They discovered that the Super Snail snacks may be associated with increased brain function. Gary is not the smartest snail in Bikini Bottom and believes he can improve his brain power by eating Super Snail Snacks. He decided to design a controlled experiment to find out whether they were right.

7. Example cont. How do Super Snail Snacks affect brain power Research Questions: Have other experiments been done on this problem? If so, what did those experiments show? How do people measure brain power?

8. Writing the Hypothesis If the Super Snail Snacks are eaten, then Gary’s test scores will increase because they improve brain function.

9. Determining Materials Materials Super Snail Snacks 2,000 Snails Pre-tests Post-tests Placebo snacks Marker ruler

10. Determing Variables and Constants Variable is any factor that can change Constants are all of the factors that are the same in both the experimental group and the control group

11. Experimental Group Include as many trials as possible in the experimental group in order to obtain reliable results In order to test this hypothesis, he recruits SpongeBob and several snail friends to help him with the experiment. 1,000 snails ate one Super Snail Snack with each meal every day for three weeks. SpongeBob created a test and gave it to the snails before they started eating the snacks as well as after three weeks.

12. Control Group Design a control group that is the same as the experimental group in every way possible, except for the factor you wish to test. 1,000 snails ate one placebo snack with each meal every day for three weeks. SpongeBob created a test and gave it to the snails before they started eating the snacks as well as after three weeks.

13. Independent Variable The factor that you wish to test Ex) Super Snail Snacks

14. Dependent Variable The factor that you measure to gather results. Ex) Test Scores

15. Operational Definition A description of the one particular way in which you will measure the dependent variable Ex) Eating Super Snail Snack – Independent variable Percentage on Tests – dependent variable *Percentage of test scores after eating Super Snail Snacks*

16. Writing a Procedure Procedure: 1. Take a IQ pre-test. 2. Divide snails into two groups. 3. Give one group one snail snack with each meal every day for three weeks. 4. Give the other group one placebo snack with each meal every day for three weeks. 5. Give each snail a IQ post-test.

17. Recording Observations Once you have obtained all of your materials and your procedure has been approved, you can begin making experimental observations. Gather both quantitative and qualitative data. If something goes wrong during your procedure, make sure you record that too.

18. Summarizing Results Test Results SnailBeforeAfter Gary64%80% Larry78% Barry84% Terry72%70%

19. Drawing Conclusions To draw conclusions from your experiment, first write your results. Then compare your results with your hypothesis. Do your results support your hypothesis? Be careful not to make inferences about factors that you did not test.

20. Results and Inferences The results of my experiment show that some of the snails benefited from the Super Snail Snacks, but most did not. My hypothesis was not supported. I infer that it is not possible to improve brain function by eating Super Snail Snacks.

21. Questions for Further Research Could the gains shown by some of the snails have been due to other factors?

22. Communicate the Results Write a Lab Report