Three page lab on Evaporation. This lab usings a homemade "scale" (you need to make) to measure the rate of evaporation of two different sponges. One sponge is the control and the other is the experimental group. This lab test wind, external hear, internal heat, surface area, and humidity. This is an excellent lab for a physical science or Earth Science teacher. Home scale is easy to make and lab shows a good diagram on what it looks like.