Fair tests and variables
In fair tests, only one thing should change — like light or speed — while all other things stay the same. This helps you know if that one thing caused the result.
See worked examples
In science class, Jonah asks: If Maya wants to test how much light affects plant growth, what should she do?
- Use different types of soil for each
- Give all plants the same light
- Change only the light amount (right)
Kai and Eli are curious. Leo wants to see if a plant grows better with sunlight or in the dark. What should he do to make the test fair?
- Keep water and soil the same (right)
- Use different types of soil for each plant
- Give more sunlight to both plants
In science class, Felix asks: If Maya wants to test how much light affects plant growth, what should she do?
- Change only the light amount (right)
- Use different types of soil for each
- Give all plants the same light
Tip: In fair tests, only one thing should change — like light or speed — while all other things stay the same. This helps you know if that one thing caused the result.
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