VOI.. 5, No. 4
LABOMTORY INSTR~CTION IN CHEMISTRY
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EFFICIENT LABORATORY INSTRUCTION IN CHEMISTRY* HERBERT R. Snnrm, LAKEVmw HIGHScnooL, CHICAGO. ILLINOIS
The expense for laboratory equipment in the teaching of chemistry is greater on the average than that for any of the other sciences. The present equipment for chemistry is not adaptable for the teaching of other sciences. These two facts prevent chemistry from being offered as a study in the smaller high schools, where there are not sufficient classes to keep the equipment in use most of the school day. It is decidedly unfair to deny a student the opportunity to study chemistry in this modern age because he happens to be a member of a small school, so we wish to present a remedy for this situation and a t the same time emphasize the proper function of laboratory training. We have no theories to offer. By trial and test of experimental use during a fifteen-year period a t Lake View High School we have crystallized opinions into facts or fiction and discarded the latter. We have two laboratories of standard equipment for individual pupil use but our pupils "are as sick that surfeit with too much as they that starve with nothing." Our chief objective is to train pupils to discover facts and solve problems by the scientific method, but without definite training in how to use the equipment provided, our pupils know no more than they who have none. If acquiring information is the aim, then those who depend entirely on the textbook are superior to those who have had laboratory practice, when equal periods of time are used. Then, why have the laboratory with its expense in equipment and pupils' time? The laboratory method i s the only effectiue way to train $u@'ls to think and discover facts. This is the real objective in all education but it is so easy to allow the acquiring of information to usurp its place. Where pupils have the free use of a textbook and have laboratory practice, those who rate above 80% in grade-with an only occasional exception-rely on verbal memory of what was read from the text rather than on what was experienced by actual contact with facts. The reason for this condition is soon found. Almost all pupil effort in the various subjects is directed to book-learning. They are told by the book what to believe and what to say. Their recitations are repetitions of phrases from the book. Few and far between are the cases where they have of their own initiative or have been required to consider evidence as a basis for deriving beliefs or judgments. When pupils come to experimental practice they see the results as the book described them, and not as they observed them. Experience is continually discounted by what they read. Do you college professors expect to find research workers among high* Paper read before the Division of Chemical Education at the 74th meeting of the American Chemical Society at Detroit, Mich., September 7, 1927.
460
JOURNAL OW CHEMICAL EDUCATION
APRIL,1928
school pupils so misguided? Is there anything that can justify such antiscientific procedure? We find the average textbook in chemistry of more detriment than value in realizing our objective of training pupils to think. There is little in it that requires thinking of the pupil and most of them even tell all the properties of substances so there is noth'mg to observe in the experimental work. With textbooks so constituted we may state the laboratory objective as: a method of disposing of chemicals without value received. An evidence of improvement is to be found in some recent textbooks that do not tell the pupils what they can learn by their own observation. It is a pleasure to know that there are teachers who believe that their pupils are able and willing to work out their education in preference to having i t furnished to them "ready-made." At Lake View we have discontinued the use of textbooks as they are now constituted, and have prepared directions for the experimental study of chemistry in project form. I n these we make clear what the scientific method is and its value. Pupils are trained to practice it as a means of acquiring information from facts without personal bias, and as a means of solving the problems of life in any field. The banishing of the textbook leaves the pupil literally "at sea without a compass," when introduced to laboratory practice without special training. The other science subjects studied previous to chemistry have given the pupils little or no knowledge of the scientific method. Those who succeed a t the start by the laboratory method do so from inherent ability rather than from training. Hence an initial period of training in how to study by the experimental method is necessary. Without this training the result of laboratory work is the same either in case of using a text or doing without. Nothing of value i s learned. The only difference is that with a textbook the instructor thinks the pupils are learning; without it he has no such illusion. He knows they are not. Of these two alternatives good pedagogy would choose the latter as the lesser of the two evils. The manner of training for laboratory work was reported to this division a t the Philadelphia meeting last year,l as the Lake View Group Method. Briefly summarized it is as follows: After a short period of general training each class is divided into two groups on the basis of effective work. Those who are dective (10 to 30% depending on the class) work individually and compose group A. The others, group B, are those who cannot or will not learn effectively by the laboratory method under their own management. Two of this group direct the experimental work with the others around as observers. The instructor gives his whole time to questioning, emphasizing fundamentals, and preserving a student attitude towards 1 THIS JOURNAL, 3, 307-12 (March, 1926); and 4, 359-63 (March, 1927).
VOL.5, NO. 4
LABORATORY INSTRUCTION IN CHEMISTRY
461
the work. Each one makes a neat written record of the work. The tests the following day show mastery of work equal to that of the group A. After another year's careful testing of this plan we are able to state the following conclusions, regarding the values of this method, with some degree of certainty. 1. The students in group B, most in need of mental exercise, receive it. They are told answers only after an effort on their part. 2. The instructor has an intimate knowledge of each pupil's effort. No copying, no dishonesty. 3. Close supervision by the instructor isnecessary for an increasing number of pupils who have few disciplinary factors in their previous training. 4. Understanding of fundamentals is thorough. The records of results are accurate and complete. All that remains is the entry of credit by the instructor. No errors to correct and laboriously explain to various pupils. 5. As pupils become proficient they are allowed to study under their own direction in group A, which is a definite incentive to effort and independence. Those of group A who show lack of effort are transferred to group B. 6. Less material and equipment are needed under the group plan. There is no good reason for any school to omit chemistry because of expense or because of not having a fully equipped laboratory. The apparatus and materials for all desirable individual experiments are inexpensive. In all others what would suffice for one person is sufficient for the group. Chemistry can he effectively taught with as little expense as any science. Efficiency is determined by the use of the equipment and not necessarily by the quantity of it.
