Basic paper towel science projects include testing for the strongest and most absorbent paper towel brand and testing for paper towel filtration capabilities. Complex projects involve lining foam cups with paper towels and placing fast-growing seeds between the cups and towels to see which towels grow the best plants.
Testing for absorbency involves pouring water into a beaker, dipping different paper towels in the beaker and calculating the volume of water displaced by each towel. To test for strength, stretch different brands of paper towels over separate jars, pour equal volumes of water on their surfaces, and add pennies on top of the towels. Note how many pennies each towel supports before it breaks.