Science: Fair Tests What Should Stay the Same
Learning how to keep experiments fair
Science: Fair Tests What Should Stay the Same
Learning how to keep experiments fair
Science - Grade 2-3
- 1
Mia wants to find out which paper towel brand soaks up the most water. She tests two brands. What should stay the same in her test?
Think about what might change how much water a paper towel can soak up.
Mia should use the same amount of water and the same size piece of paper towel for each brand. This helps make the test fair. - 2
Leo wants to know which toy car rolls the farthest. He tests a red car and a blue car on a ramp. Name two things that should stay the same.
Think about what could make a car roll farther besides the car itself.
The ramp height and the starting place should stay the same. This way, only the toy car is being tested. - 3
A class is testing which plant grows best: one in sunlight or one in shade. What should stay the same for both plants?
Both plants should get the same amount of water, the same kind of soil, and the same size pot. The light is the thing being changed. - 4
Sam wants to test whether warm water or cold water dissolves sugar faster. What should stay the same?
The test is about temperature, so other things should be kept equal.
Sam should use the same amount of water, the same amount of sugar, and the same kind of cup. The water temperature is the only thing that should change. - 5
A student drops a ball from different heights to see if height changes how high it bounces. What should stay the same each time?
The student should use the same ball and the same floor each time. The drop height is the part being changed. - 6
Nora tests which magnet picks up the most paper clips. She uses a small magnet and a large magnet. What should stay the same?
Paper clips can be different sizes or materials.
Nora should use the same kind of paper clips and give each magnet the same amount of time to pick them up. This makes the comparison fair. - 7
Which sentence describes a fair test? A. I test one seed with lots of water and another seed with no water in different soils. B. I test two seeds in the same soil and give one more water than the other.
Sentence B describes a fairer test because the soil stays the same and the amount of water changes. A fair test changes only one main thing. - 8
A class wants to find out which ice cube melts faster: one on a plate or one on a towel. What should stay the same?
Think about what else can make ice melt faster.
The ice cubes should be the same size, and they should start melting at the same time in the same room. The surface is the thing being tested. - 9
Jay tests whether a paper airplane made from thick paper flies farther than one made from thin paper. What should stay the same?
The test should not be about who throws harder.
Jay should use the same airplane shape, the same throwing strength, and the same starting line. The type of paper is what changes. - 10
A student wants to know if a flashlight works better with Brand A batteries or Brand B batteries. What should stay the same?
The student should use the same flashlight and the same number of batteries for each test. The battery brand is the only thing that should change. - 11
Two cups of water are placed outside. One cup is covered with plastic wrap and one cup is left open. The student wants to see which cup loses more water. What should stay the same?
Start with equal cups so the ending amounts can be compared.
The cups should be the same size and have the same amount of water at the start. They should be placed in the same area outside. - 12
A class tests which type of soil lets water pass through fastest: sand or garden soil. What should stay the same?
A different amount of soil could change how fast water moves.
The class should use the same amount of soil, the same amount of water, and the same kind of container. The soil type is the thing being tested. - 13
Why is it important to keep some things the same in a science test?
It is important to keep some things the same so the test is fair. Then the scientist can tell which change caused the result.