The Zimbabwe Secondary School Science Project (ZIM-SCI) developed student study guides, corresponding teaching guides, and science kits for a low-cost science course which could be taught during the first 2 years of secondary school without the aid of qualified teachers and conventional laboratories. This ZIM-SCI study guide presents activities and short experiments for a four-part unit which traces the path of energy found in food. Areas investigated include: (1) food chains and food webs (introducing producers, consumers, and decomposers); (2) organisms found in milk; (3) compost and fertilizers; (4) nature and identification of fats and proteins; (5) diets; (6) balanced meals; (7) energy measurement in joules; (8) digestive systems, focusing on the human system; and (9) anatomy and physiology of human teeth. Information is provided throughout the unit to help students understand the scientific concepts behind the activities and experiments. (JN)