1. Scientific Method Notes 8th Grade Science September 14, 2010 Ms. McKinley

2. What is the Scientific Method? • The process that scientists use to solve real-world problems or answer real-world questions.

3. Think-Pair-Share WHAT problem have we looked at so far in this class? (OR, what question have we tried to answer in this class?)

4. Observation/Problem Steps in the Scientific Method Ask a Question • WARNING!! This is not always a step by step process. Sometimes you add steps, sometimes you go back to a certain step. This is a simple model. Form a Hypothesis Test the Hypothesis Analyze Results/ Draw Conclusion

5. Scientific Questions • MUST be TESTABLE • This means you should be able to design an experiment that would help to answer the question.

6. YOU decide:Which ones are “TESTABLE”? • Which brand of skateboard is better? • Which brand of skateboard is the strongest? • Should I paint my bike? • What happens when you leave a bike in the rain? • Which brand of cleaner works best? • Which kind of plant food makes plants grow the most? • Which exercise program will help me lose the most weight? • Why do dogs bark? • Why do babies cry? • What types of objects fly?

7. Form a Hypothesis • Your answer to a scientific question. • An explanation that can be tested w/ a scientific experiment

8. Think-Pair-Share What VARIABLES were in the BrainPop video experiment? What VARIABLES were in Lab #1 (Paper Airplane Lab)?

9. Testing your Hypothesis • As the scientist, you decide: • What you will do • What you are looking for • What you will measure • Variables • Anything that can vary in your experiment. • Constants • What does not change in your experiment.

10. Variables: 2 Types • Independent (IV): • The factor you want to test. • EXAMPLE: The type of paper used • Dependent (DV): • The factor you measure or observe. • EXAMPLE: The distance each plane flew

11. Let’s look at an example… • You have just been hired as a skate deck designer at Element skateboards. • Your first job is to answer the following question: • How does changing the material in a skateboard deck affect a skater’s ollie height?

12. Experiment setup • You design a new skateboard deck that has a special layer built inside. • You will test to see if this special layer makes any difference on ollie height.

13. Experiment setup: • You bring in 10 skaters and split them up into two groups of 5: • GROUP A (experimental group) gets a new, modified Element skateboard WITH the special layer. • GROUP B (control group) gets a new, unmodified Element skateboard WITHOUT the special layer. • Both skateboard types are the SAME style, color, shape, size, wheels, trucks, same everything. • Only difference is the special layer in the deck. So far, what are the CONTROLS in this experiment?

14. Set up continued.. • Have all skaters skate around on their new boards for 3o min to get used to them. • Then, test each skater’s ollie height. • For each skater, measure ollie height in meters. Do this 5 times, and calculate the average height.

15. Stop, and think about it… • Skateboard design experiment example: • IV: • DV: • Constants:

16. Stop, and think about it… • Skateboard design experiment example: • IV: • Skateboard design type (modified or unmodified) • DV: • Ollie height (meters) • Controls • All skaters get new board • Same shape, size, wheels, trucks, etc.

17. What are some things we should be careful of?

18. Getting accurate data • Experimental vs. Control groups • Experimental: IV changes • Control: IV does not change • Multiple Trials • Do the test several times