1. Variables in Science Experiments
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2. Control The part of the experiment that does not change
The results of the experiment are compared to the “control group”
Example: If you want to know how sugar impacts hyperactivity, you need a CONTROL GROUP in which no one eats any sugar to compare to the group who ate a lot of sugar to see if their actions are different

3. Independent and Dependant Variables
Independent variable: The variable the experiment is designed to test (it can be changed by you, the experimenter, over the course of the experiment)
Dependant variable: The factor that responds to changes in the independent variable. It is what the experiment is trying to measure.

4. Examples
Your experiment is on plant growth. You decide to expose different plants to sunlight for 5 hours each day and measure which plant grows the tallest over one month.
Circle the Independent variable
Underline the Dependant variable