Variables in Experiments

What You'll Learn

Variables in experiments include the independent variable (what you change), dependent variable (what you measure), and controlled variables (what you keep the same).

Key Words

hypothesis
variable

Materials Needed

pennies
plastic wrap
cardboard
tape
scissors

Safety First

Clean up spills immediately to prevent slipping.
Use materials only as directed in the experiment.
Keep small objects away from young children.

Steps

Step 1 — Read

Look at the vocabulary words and write a definition for each in your own words.

Step 2 — Do

Build a water filter using a bottle, sand, gravel, cotton, and charcoal. Pour muddy water through and measure how clear the output is.

Step 3 — Observe

Watch carefully for any changes and note the time.

Step 4 — Record

Create a data table to organize your measurements.

Check Your Understanding

Question 1

1 of 3

What is a hypothesis?