You have decided to test the effects of five garden fertilizers by applying some of each to five separate rows of radishes. what is the variable you are testing? what factors should you control? how will you measure the results?

You are testing which fertilizer makes the radishes grow the fastest.

factors you should control: sunlight exposure, water amount, fertilizer amount.

Measure: check the rows of radishes to see how much each row has grown in comparison to the others. Whichever row with the healthiest radishes has the best fertilizer.