An EXPERIMENT in VISUAL EDUCATION* J. 0. FRANK State Teachers' College, Oshkosh, Wisfonsin
The existing literature dealing with studies of the use of lantern slides in elementary chemical instruction reports a variety of results and conclusions. It is suggested that variables which have not received suficient attention are: (1) the nature of the slides presented and (2) the method of presentation. The present study arrives at some tentative conclusions as to the kinds of slides which are effective as teaching aids. Sets of slides selected on the basis of these conclusions have led to increased achievement in the writer's classes.
types and led to a search of the literature for reports of investigations in this field. Many items of value were found, though only one is of particular interest here. Reports of studies of the effectiveness of the use of lantern slides in teaching chemistry and other sciences indicate a variety of results. I t seems that slides are of great aid to some teachers and of little or no value to others. It is true that most studies are reported in such a way that we are left in doubt as to what kinds of slides were used and also as to how they were used. This disagreement of investigators as to the effective+ + + + + + ness of slides aroused our interest and led to a scrutiny NY one who makes a study of advances in meth- of the more than three hundred slides in our chemistry ods of teaching science is certain to be impressed department, with a view to evaluating and classifying by the increasing attention now given to visual them on the basis of their real teaching value. The aids of all kinds. Many teachers who have been using question of the method of using slides was also of incharts, models, graphs, slides, pictures, and the like for terest, but this was left for a later study. decades are now awakening to the fact that visual aids Preliminary tests on our own students gave us a to teaching promise to play a part of greatly increased number of worth-while facts and ideas. Students in importance during the next few years. the general chemistry class were almost unanimous in During the past two years the writer has added film their preference for the showing of all the slides relating slides and moving pictures to the usual battery of visual to a unit in chemistry at the beginning of the unit aids. When a moving-picture projector was installed in connection with a lecture covering the fundamentals it became necessary to determine the amount of time of the unit. It was decided to adopt this one method of to be given to moving pictures and to consider methods using our slides and to solicit student criticism in an of coordinating them with other visual aids to classroom attempt to evaluate the slides which had already been and laboratory teaching. This opened the whole used in the general chemistry class. About one hunquestion of the effectiveness of visual aids of various dred seventy slides were shown the class for the second TPresented before the Division of Education of time. Several students displayed a very keen critical the A. C. S. at Denver, Colorado, August 23, 1932. sense, and many good ideas were obtained in this way.
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At the same time, several sets of slides sent out by industrial concerns were secured and studied It soon became apparent that some slides had no teaching value whatever if evaluated in terms of their contribution to the stated objectives of the unit with which they were to be used. Other slides aided in inducing interest in the subject matter of the unit, but seemed to have no other value. Some of the slides in the industrial sets apparently were designed purely for advertising purposes. On the other hand, some of the industrial sets were of great value indeed, often being superior to the standard slides which were presumably produced solely for teaching purposes. In only one case, the iron and steel unit, was there a complete set of slides covering the entire unit and contributing to practically all the objectives of the unit. In all other cases, slides were available to aid in teaching only a part of the items of the unit, or else the available slides were ineffective in teaching essential parts where effective aid was almost a necessity. In some cases the sets of slides actually succeeded in avoiding every essential part of the unit and taught nothing at all of value. In the light of criticism from about forty studelits the following tentative conclusions were reached: (1) Students greatly prefer to see a set of slides and to hear a complete lecture at the beginning of a unit rather than later. (2) A whole set of slides covering a given unit is better received and given more attention by students than a few slides shown at intervals or covering only a few items. (From a practical teaching standpoint a complete set is more to be desired by the teacher as well.) (3) Slides used in teaching chemistry vary enormously in their teaching value. Many slides in standard sets, and sometimes entire sets, are wholly worthless as teaching aids. Sometimes the slides offered for sale in standard sets are intended to aid in teaching processes or showing industrial methods and apparatus which have been obsolete for years. (4) One of the greatest values resulting from the use of slides lies in the interest they induce. Some slides which seemed to have little teaching value were rated highly by students because they made the subject matter of the unit more interesting. (5) When either charts or tables can be used to teach a given item, the students prefer the charts. When diagrams or tables can be used, they prefer the diagrams. Yet when the essential figures in a table can be made conspicuous in some way or other, the students claim that they do learn easily from the tables. Students prefer historical data presented in tabular form by means of a slide rather than in story form on the printed page. (6) Students believe they learn more from slides
canying printed captions and printed notations labeling the various important features of the apparatus, device, or process shown by means of slides. Lettered parts are difficult to read and understand unless much time is given. (7) Students have considerable difficulty in reading script on a slide, no matter how clearly it may be written. Hand-lettering is more legible than script, and typewritten material more legible than handlettering. Boldface print seems to be more legible than any other form of lettering. (8) One great value of slides lies in the fact that time enough can be given an item so that its details can be mastered. Students were unanimous in quoting this as one of the important advantages of slides. (9) I t is evident that slides are not equal to charts for showing apparatus of intricate design, or other material which has to remain in view for a considerable time. In an effort to secure further data on the effectiveness of various types of slides and to verify some of the tentative conclusions mentioned above, it was decided to prepare several sets of slides which were free from all of the objections found in many of the conventional slides, and to try these out in high-school and college classes. Five sets of slides were begun, and four sets were carried to practical completion. "Sulfur," "Sugar," "Iron and Steel," and "Aluminum" were the subjects or units for which sets were prepared. The iron and steel and the aluminum sets were very complete and made with considerable care. These two sets were used exactly as the old ones had been used in the same type of class the previous year. No other variable was present in the method of teaching used. The accomplishment of the class was about 14% greater than that of the previous class on each of these two units, though the second class had averaged a little less than the previous class in general accomplishment up to the time of the trial of the slides. The interest of the class in the experiment probably accounted for a part of the increased accomplishment, but it seems safe to conclude that the slides, prepared especially to aid in teaching the specific items desired, did actually render more than usual assistance in the teaching of these two units. It seems probable that the conflicting findings of investigations of the effectiveness of slides in the teaching of science are partially due, at least, to Merences in the teaching value of the slides themselves, and probably also in the methods of using them. The results from this small and rather unscientific experiment seem to indicate a need for an extensive investigation to determine how to prepare slides which will render more effective aid in chemistry teaching, and to determine just how slides may be used most effectively.
