2. Scientific Method How can we determine if something is a fact or an opinion? How do we determine the answer to a problem? The answer is the scientific method!

3. Scientific Method: An organized approach to solving problems  Step 1: Identify the problem or question. Make sure only one variable is being tested.  Step 2: Research Gain knowledge and use all available resources to collect info. Ex: Internet, books, and libraries.  Step 3: Form a Hypothesis. Educated guess based on your research. Predicts the relationship between cause and effect

4.  Step 4: Design a controlled experiment. A. Control Group: Comparison (No variable given) B. The experimental variable group. This variable is being tested and causes measurable effects. C. Independent variable: Variable to test Ex: The amount of fertilizer given to a plant D. Dependent variable: Responds to independent variable Ex: Plant Height is dependent upon the amount of fertilizer it is given. The change in height would be the dependent variable.

5.  Step 5: Analyze the data and come up with a conclusion. If the experiment supports the hypothesis, the hypothesis “was supported”. If the experiment does not support the hypothesis, the hypothesis, “was not supported”

6. Characteristics of a good/valid experiment: Controlled Tests one variable at a time Has a large sample size (many test subjects) Repeatable with the same results

7. Control Group Serves as a basis for comparison Differs in the one variable being tested (No variable given) Ex: Control Group- Water Experimental group- Water with hormones added

8. Control Group for vaccine/drug testing Control group is given a placebo Placebo (in place of the medicine)- Sugar pill (does not contain vaccine or drug/medicine)

9. Control Cup: Place a piece of masking tape on the cup with the names of each group member Label the cup, CONTROL:WATER Fill the cup half-way with potting soil Place 1 seed in the soil Cover the seed with more potting soil but leave about 2.5 cm at the top of the cup Measure 10mL of water in the graduated cylinder and water your seeds!

10. Variable Cup: Place a piece of masking tape on the cup with the names of each group member Label the cup, VARIABLE: Fill the cup half-way with potting soil Place 1 seed in the soil Cover the seed with more potting soil but leave about 2.5 cm at the top of the cup Choose an amount of the variable substance, no more than 15 ml, measure that amount and feed your seeds!

11. Complete the Design an Experiment (Follow up Sheets) Remember to fill in information specific to your Experimental Design!