📗 The use of audio-visual aids to learning is far from new in the American educational system, but it has been given a tremendous imepetus by the war and the striking success of all branches of the Armed Forces, especially the Navy, in speeding training by their use. This small book is concerned with one of the most important phases of audio-visual aids in the classroom-the utilization of the educational sound film. It reports the results of an extensive experiment in this field, in which three controlled groups in the 4th, 5th, and 6th grades were tested on 27 Encyclopaedia Britannica films presented by different methods. The results of these tests showed a 50% better achievement with the use of some of the tested teaching methods described here, and a further 50% improvement with the complete use of exact teaching steps. The basis for sound instruction methods in the use of the text-film is clearly outlined here, and the book constitutes the most authoritative statement so far available of the utilization of educational sound films. It will be of special importance to teachers who use such films and in courses in audio-visual aids.