But progress in the development of the new medium was slow. The projectors were the 35mm. type, too expensive and much too cumbersome for classroom use. The few 35mm. sound films then available hardly justified the expenditure, in most cases $1oo a reel.
The development of the i6mm. sound film projector opened up new possibilities for the use of films in classroom teaching. About 193o, i6mm. sound-on-disk projectors appeared on the market. This type of projector was superseded in 1933 by the i6mm. sound-on-film projector, more compact and efficient. Improve ments have been added until, in 5939, there were efficient models ranging from the small projector for classrooms to the large, arc illuminated model for auditoriums. Design has been perfected to the extent that teachers and older students can operate the projec tor competently.
The i6mm. film, now largely accepted as standard for schools, is printed on safety stock, that is, the slow-burning acetate type.
Technical refinements in 16mm. sound films have kept pace with improvements in projectors. Securing satisfactory sound quality from the small sound track space allowed by the i6mm. film was a real achievement. The next step, already presaged, will be the satisfactory and inexpensive use of colour in Omm. film prints.
Erpi Classroom Films, Inc., formerly the educational depart ment of Electrical Research Products, Inc., is the major educa tional film producer, releasing about 24 new films a year. Their films deal mainly with science, music, and the social studies.
Films which have definite educational value are being produced by governmental agencies, industrial concerns, and various pub lic welfare groups. The Plow that Broke the Plains and The River are excellent examples of documentary films produced by govern mental agencies. The University of Minnesota is engaged in an educational film production program. Another type of film source, growing steadily in 'importance, is found in the films made by teachers and students in local schools.
A number of feature films have recently been edited for school use, under the auspices of the Commission on Human Relations of the Progressive Education Association. These films are being used experimentally in selected schools and may later be distrib uted generally. Certain other feature pictures of educational value have been placed in i6mm. form and are available to schools through various distributing agencies.
A problem of major importance today is that of distribution. Many schools cannot afford to purchase an adequate library of educational films (about $45 a reel). The alternatives are to rent and borrow films, or to form co-operative film libraries with near by school systems. The American Council on Education has planned a series of experimental units in cities, counties, colleges, and States, to study the types of distribution facilities best adapted to various kinds of local needs. One outgrowth of this attention has been the establishment of a non-profit distribution agency, the Association of School Film Libraries.
Another major problem is that of training teachers to utilize films effectively. The motion picture may lose much of its poten tial contribution if the teacher fails to integrate it with the needs, interests, and activities of the students. There has been a significant increase in teacher training courses, and in the pro fessional literature dealing with film instruction methods.
There is a growing tendency to initiate programs of audio visual instruction in school systems, rather than to rely upon the efforts of a few scattered teachers. A program planned to meet local needs, involves training teachers in film usage, selecting films in terms of the curriculum, providing adequate equipment for showing films readily, and developing competent administra tion of routine clerical and mechanical aspects.
The educational film today assumes particular importance as an aid to learning. The wide range and complexity of the modern curriculum, the emphasis on functional social concepts and ex perience, and the attention to the individual learner, all re quire teaching material that is vivid, real, and time-saving. The motion picture, carefully produced and skilfully used, offers special contributions to learning. It can bring vicarious ex perience from all over the world into the classroom. Through slow-motion, time-lapse, microphotography, and animated draw ing, processes may be studied to unusual advantage. The addition of sound provides another essential element of reality, or permits the recording of an expert commentary. As a dramatic medium of expression, it may create attitudes and appreciations. Current researches in the production and utilization of the educational motion picture should add still more to its significance for in struction.