The Life Starter
Sign up
Grade 2 · lesson 1 of 4

Read a Fair Plant Test

Identify a comparison that changes one condition while keeping others the same.

Download the grade pack

Supplied materials

  • Paper and a pencil, or say your answers aloud.

Learn the idea

A fair comparison changes one condition at a time. If we change both light and water, a result cannot tell us which change mattered. Real plants vary, so repeated tests are stronger evidence than a single pair.

Use these fictional notes, without growing or harming a plant: pots A and B have the same kind of seedling, soil, starting height, light, and test length. A gets the planned water; B gets no water. After one week, A has new leaves and B has wilted. These notes compare water, not light.

  1. List what was the same for A and B.
  2. Circle the condition that differed: water.
  3. Describe the recorded result without inventing numbers.
  4. Use the check to plan a separate comparison about light.
Worked example

See the method in action

A and B help test the effect of water because light was the same. They do not separately test the effect of light.

Your turn

Check your reasoning

Your answer is temporary and is not saved to an account. Download your current answer before leaving or reloading. Written work on paper or in another app stays in your own file.

Which pair would best compare light while changing only that condition?

Feedback appears here after you check. This is practice, not a graded school assessment.

See the answer and explanation

Use the same seedling type, starting size, pot size, soil, water, and test length, but place one pot in light and one in darkness.

The light condition changes while water and soil stay the same. Changing several conditions would make it harder to explain a result; changing none would not compare light levels.

Take it further

For the proposed light test, also keep seedling type, starting size, pot size, and test length the same. Explain why using several plants in each group would give better evidence.

Nothing here is saved to an account or sent to a teacher. The answer download includes your current choice and any checked feedback.

Check the subject sources

These LifeStarter passages, scenarios and exercises are authored for this Academy with AI assistance and review. External resources keep their publishers’ terms. A grade label suggests a starting level; it does not establish alignment with your school’s complete requirements.