This week, third graders measured and cut equal-area sample sizes from each brand of paper towel. We discovered that even though manufacturers typically list the amount in each roll in terms of square feet, that paper towel rolls are actually only 11 inches in height. The school's towel rolls are 7 inches in height. We had to do some division to find an approximate length so that our sample sizes would each be one square foot in area.
The next step in this experiment is to test absorption by thoroughly soaking each sample and then comparing its wet weight to its dry weight.