Find out which paper towel brand is the strongest with a penny experiment. Buy a variety of paper towel brands and rip off a sheet of each one. Make sure all the sheets are about the same length. One at a time, moisten the paper towels with a spray bottle until they are wet but not dripping. Have a friend hold the paper towel taunt in his hands. Place one penny at a time into the center of the paper towel. Count how many pennies each paper towel can hold before breaking. The one that holds the most will be the strongest.
Experiment with different placements of pennies to find out which design will help the paper towel better hold the weight. Wet a paper towel and have someone hold it tautly between her hands. Count how many pennies you can stack in the center of the paper towel, one on top of the next, before it breaks. Next, create a spiral design with pennies in the center of another wet paper towel, again counting how many it can hold before breaking. Test different penny placements to see which distribution best helps the paper towel hold the weight.
Test how a paper towel's strength varies depending on how taut it is. Wet a paper towel and hold it between your hands as tightly as you can without breaking it. Have a friend place pennies on the paper one at a time, counting each one, until the paper towel breaks. Hold another paper towel between your hands, this time with some slight slack in the center, and again repeat the penny test. Finally, hold a wet paper towel loosely between your hands so that it creates a cradle to see how many pennies it can hold. Analyze which method was able to hold the most pennies and why.
See if the type of liquid affects a wet paper towel's strength. Using only one brand of paper towel, wet one sheet with plain water. Conduct the penny test, placing one coin on the taut towel at a time, and count how many it can hold. Next, wet another sheet with soapy water and repeat the experiment. Wet paper towels with a variety of liquids -- including soda, juice and milk -- to see if the type of liquid makes a difference in the paper towel's strength.