Fair Test

Key Stage 1

Meaning

A fair test is an experiment where we make sure the results are not affected by other things.

Key Stage 2

Meaning

A fair test is an experiment where we only change one variable to make sure our results only depend on what we chose to change.

About Fair Tests

There are many ways to make a test unfair.

If we wanted to see who is the fastest in class we would do a fair test where we would make sure everyone is wearing shoes, no-one is wearing their school bag and everyone has to run the same distant. The test would not be fair if some people weren't allowed to wear shoes or some had to wear their school bags.

If we wanted to know which dissolves best sand, salt, flour or sugar in a fair test we would make sure we used the same amount of water, the same amount of each powder and stir them for the same amount of time. The test would not be fair if we used different amounts of water each time, or a different amount of powder or didn't stir some of them.

In a fair test you can trust the results. If an experiment is not a fair test then you cannot believe your results because they may be caused by you changing something else.

Key Stage 3

Meaning

A fair test is an experiment in which only one variable, the independent variable, is changed to make sure results are only affected by the independent variable.

About Fair Tests

An experiment can be made a fair test with Control Variables. If there are enough Control Variables then only the independent variable will be able to affect the dependent variable.

Key Stage 4

Meaning

A fair test is an experiment in which only one variable, the independent variable, is changed to make sure results are only affected by the independent variable.