This study aims to develop home economics teaching materials to enhance students' understanding of the role of enzymes contained in natural microorganisms and food. As experimental material, a trial viscometer, based on Stokes' law, was offered to measure the enzymatic activity at 29.5℃. This experimental system could be compared with the enzymatic activity of many foods. Papain and gelatin (3% solution) were used for the standard enzyme and solute respectively. From the results, an index of activity for enzymes was experimentally established. This was applied comparatively to 63 foods and 2 medicines. In connection with enzymatic activity, a learning unit was proposed "The Role of Enzymes in Food in Life", including effect on cooking methods; combination of food materials; and role in the cooking or preservation of traditional foods.