A Simple Indication of the Efficacy of a Teaching Device

Abstract

Food from the Sun* is a vivid presentation of photosynthesis, including many ways living things respond to direct and indirect sunlight. It contains much basic physiological and organic chemistry, centered around foodstuffs, the manufacture and uses of sugars in particular. Although geared in appeal to secondary school or lesser levels it holds the attention of older people. We are so conscious of light and its many influences that it is not unusual to find much general infornmation at hand about the photosynthetic process. If there is anything about plants which students of general science or biology know in part when they arrive at college it is chlorophyll. Plant metabolism has received considerable attention. Chlorophyllbearing structures are considered important. At an annual session of NABT which covered teaching implementation an excellent talk was heard on the role of sugars in animal and plant life. Food from the Sun was shown, samples of the film strip being distributed. Two of the author's course objectives have been (a) to share with classes benefits gained from trips and meetings; (b) to review vital ideas previous to mid-year examinations. Therefore this series of still pictures was projected before General Biology students on the final day of formal first-semester work. In the examination of the succeeding Friday, about 48 hours thereafter, 62 questions were asked, evaluated at 1-5 points each. The student selected for a total of 100 credits what he chose to answer. Inserted in the test was the following option: What 4 facts or points do you recall from the film strip of Wednesday last? Thirty-eight answered the question. Two mistakenly used a moving picture film on amoeba, shown previously, as the basis for reply. Several times during the semester metabolism in chlorophyll-bearers was discussed. Some weeks, however, had passed since mention of it. A rather thorough consideration, therefore, was accorded the topic. From the papers only those statements specifically individual and clearly identifiable with the pictures seen are chosen. The broad idea itself could suggest facts, of course. But the stills are rather striking, full of action and color, well calculated to make lasting impress. Did they do so? Tabulation of the data shows topical summaries with number of times mentioned.