What is the Scientific Method? An organized set of steps used to solve a problem. Is there a certain number of sets? NO! It is simply a logical way to solve a problem.

Can you form conclusions about something before you test it? NO! Can you form conclusions about something before you state a hypothesis? NO!

EXAMPLE (1) Observation: Something done through the five senses. - “My shampoo doesn’t clean my hair!” (2)State the problem: - “I need a shampoo that will clean my hair better.”

(3) Form a Hypothesis: - “If I use “Pert” instead of “Suave,” then my hair will feel cleaner.” (4) Test the Hypothesis through an experiment: -How could I set up this experiment?

GOOD Performing a GOOD experiment Question: What makes an experiment a GOOD experiment? Answer: It truly tests for what it is supposed to test for. Question: How can we make sure that our experiment is a GOOD experiment?

GOOD Setting up a GOOD experiment Rules: (1) An experiment usually contains two variables. What’s a variable? Something that can change...or have more than a single value. Two variables: –(1) Independent Variable (manipulated) –(2) Dependent Variable (responding)

What are the variables in our experiment? Independent Variable: What the experimenter..YOU.. changes. Types of Shampoo. What do think will happen if we change the types of shampoo? Our hair will be cleaner. So, the Dependent variable is the “Feel of our hair.”

GOOD Setting up a GOOD experiment Rules: (2) All experiments need a control. A control is something to compare the experiment to. What’s our control? Our regular shampoo. “Pert”

Setting up the Experiment For two weeks we will use “Pert” and then for two weeks we will use “Suave.” How can we make sure that the shampoo is the only factor affecting how our hair feels?

1.Use the same shower. 2.Make sure temp. is the same everyday. 3.Do not put anything else on hair. 4.Either blow dry everyday or never blow dry.....why? These are called CONSTANTS. They do not change.

Why do we need Constants? To make sure we are testing for what we said we are testing for.

After the Experiment (5)Analyzing the data What did we learn? -”Pert” made my hair feel cleaner. (6)Draw conclusions. Was the hypothesis supported? YES! What does this data mean for the future? -I will use “pert”.

How can we be sure that the results are real?

What’s a theory? Scientific Theories are based on knowledge gained from many experiments. NOT A GUESS!

Homework Design an experiment that will determine whether hot water freezes faster than cold water. Make sure that all constants are controlled. What are some constants for this experiment?