Meant to be a pre-field trip lesson, this can also serve as a cute and simple activity to use when your little ones are learning about evaporation or surface area. The children cut tiny t-shirts out of paper towel material, wet them, and hang them to dry while tracking the drying time for different sizes. Note that there are no lab sheets provided; consider having older learners draw up a data table prior to experimenting. Another variation for this experiment would be to compare different types of same-sized paper towel t-shirts.