Scientific Method 1. State the Problem 2. Research develop a question you want to answer 2. Research find out what is already known about your subject, & make your own observations 3. Form a Hypothesis an educated guess or possible answer to your question that is based on your research

5. Record and Organize Data 4. Experiment set up a situation to test your hypothesis 5. Record and Organize Data keep track of your measurements and observations use graphs and data tables to identify trends in the data 6. Conclusion explain what the data means does data support hypothesis??

Hypothesis, Theory & Law needs to be tested, may or may not be correct Theory a former hypothesis that has been supported by many experiments can still be changed or discarded Law a theory that scientists are extremely confident in (ex: the law of gravity)

Key Terms Control – any factor of the experiment that does not change. Variable – any factor of the experiment that does change. Independent variable – the factor in an experiment that you test. It is different for each group. You determine it. Dependent variable – basically, it is the results of the experiment. It changes based on the independent variable. Control Group – Only one per experiment. Acts as a baseline for comparison. It is not exposed to the independent variable. Experimental Group – Can have one or more. Each should be different based on the independent variable.

Controlled Experiments Set up two or more groups for comparison Groups are set up to be alike in all ways except one The one difference between the two groups at the start of the experiment is called the “independent variable” The INdependent variable is the one you are IN control of! Experimental Group(s) is (are) exposed to the variable, the Control Group is not Significant differences in results are probably caused by the independent variable

Which experiment shows the control set-up & which shows the experimental set-up?

Characteristics of Good Experiments Use large numbers in each group, this increases the reliability of your results Validity-other scientists should be able to get similar results if they repeat your procedures Cautious Conclusions * don’t overstate the meaning of your data results could be affected by factors that you are unaware of