1. Independent vs Dependent Variables
Write on the RIGHT Side

2. Variables are factors that can change in a scientific investigation
What is a variable?
Variables are factors that can change in a scientific investigation

3. Independent Variable Also called the Test Variable
This is the factor that is deliberately manipulated (changed) in an experiment
You can determine your independent variable from your hypothesis
An experiment should have ONE independent variable
Scientists TRY to keep ALL OTHER variables constant (other variables stay the same)

4. Dependent Variable Also called the outcome variable
The factor that changes as a RESULT of manipulation of the independent variable
What you measure in an experiment

5. Examples
Identify the independent variable, dependent variable, and constants in the following questions.
How is plant height affected by the amount of sunlight it receives?
IV:
DV:
Constant:
How does a person’s heart rate change as speed of movement increases?

6. CONSTANT: STAYS THE SAME
Remember!
IV: YOU CHANGE
DV: YOU MEASURE
CONSTANT: STAYS THE SAME

7. Reflection (Write on the LEFT SIDE)
Write the questions and underline the independent variables in one color and the dependent variables in another color for each:
How do different brands of fertilizer affect plant growth?
Do sleep patterns affect student test scores?
Is weight loss impacted by different sports played?
Does sunlight exposure increase the risk of getting skin cancer?
Is your cell phone bill affected by the amount of data you use?