Variables in Experiments (Part 3)

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

straws
paper clips
rubber bands
string
cups
aluminum foil

Safety First

Protect your work surface with newspaper or plastic.

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?