Filipino scientists and inventors have tried many ways of using solar energy. One simple device, made of wood and ordinary plastic sheets, traps solar energy to dry palay grains and other agricultural products. In this module, information and activities are provided to help students: (1) learn the advantages of using a solar crop dryer over direct sun drying; (2) build a low-cost solar crop dryer; (3) compare the drying time in the dryer and in direct sun drying using palay grains; (4) measure and compare the temperature of the air inside and outside a dryer; (5) make design changes in the dryer and observe the effect on dryer time; and (6) build a dryer three times as large as the first one. Each activity includes a list of materials needed and detailed procedures. A short mastery test (with answers) is provided. (JN)