Document Type



At the beginning of the school year 140 students registered in College Physics in two sections to meet at eight and nine o'clock respectively. During the first semester four mid-semester examinations each containing 50 objective items of the multiple situation type were given. The average of the mid-semester examinations was found to correlate almost perfectly with the corrected Nationwide Examination in College Physics used as a semester final. On the basis of these achievement data it is possible to select groups at random from either section and compute their relative achievements. Using this method to predict what a given group might be expected to achieve, four separate experiments have been performed on the effectiveness of physics demonstration lectures. In two experiments the object was to see how well the students could explain theory that was developed and demonstrated by the use of lecture experiments. The same theory was partially covered in the text-book. About 40 per cent of the students were sent out of the room before the lecture. Two days later examinations showed that in proportion to their expectancy the student who did not hear the lecture or see the experiments knew fully as much about the theory and its application as did those who remained in the lecture room.

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Journal Title

Proceedings of the Iowa Academy of Science





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©1934 Iowa Academy of Science, Inc.



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