1. Understanding Control and Experimental Groups
Designing a GREAT Experiment….
Or at least one that tests the Hypothesis

2. True or False?
The way to show that a hypothesis is true or false is to design and complete an experiment.

3. What is your Hypothesis
Scientists must be careful in how they design an experiment to make sure that it tests exactly what the hypothesis states.

4. Only ONE Variable
A proper experiment compares two or more things but changes only one
variable or factor in the experiment.

5. Two Groups The Control
In order to make sure that only one factor is being changed in an experiment, the test is divided into two groups.
One group, called the control group, is exposed to the all the circumstances of the experiment but doesn’t get whatever factor is being tested in the experiment.

6. Two Groups The Experimental Group
The experimental group gets all the circumstances of the experiment plus the one variable being tested by the experiment.

7. Why have a control?
The purpose of the control group in an experiment is to provide a fair base for comparison when it’s time to analyze results.
Having a control group is one of the most important parts of conducting an accurate experiment.

8. Example: Hypothesis: Puppies that are given vitamins gain more weight.
Control group: puppies that aren’t given vitamins
Experimental group: puppies that are given vitamins

9. Your Turn……….
Work together in groups of two to finish the Worksheet
Anything you don’t finish in class is Homework, so keep on task