Students apply the concepts of conduction, convection, and radiation as they work in teams to solve two problems. One problem requires that they maintain the warm temperature of one soda can filled with water at approximately body temperature, and the other problem is to cause an identical soda can of warm water to cool as much as possible during the same thirty-minute time interval. Students design their solutions using only common everyday materials, and they record the water temperatures in their two soda cans every five minutes.