Scientific Method Notes 8 th Grade Science September

Scientific Method Notes 8 th Grade Science September 14, 2010 Ms. Mc. Kinley

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

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? )

Steps in the Scientific Method Observation/Problem Ask a Question Form a Hypothesis 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. Test the Hypothesis Analyze Results/ Draw Conclusion

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

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? 8. Why do dogs bark? 9. Why do babies cry? 10. What types of objects fly? 1. 2. 3. 4. 5. 6. 7.

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

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

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.

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

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?

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.

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?

Set up continued. . Have all skaters skate around on their new boards for 3 o min to get used to them. 2. Then, test each skater’s ollie height. 3. For each skater, measure ollie height in meters. Do this 5 times, and calculate the average height. 1.

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

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.

What are some things we should be careful of?

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