DEMONSTRATION versus

LABORATORY ONCE AGAIN ROBERT LOCKE COOKE

Wheaton College, Wheaton, Illinois

This article describes a laboratory procedure which i s a better degree of attention and retention by the class than neither the standard laboratory nor lecture demonstration teacher demonstration seems to produce. method but which seems to offer tthe advantages of each + + + + + + while lacking some of their disadvantages. I t involves pupil demonstration by a systenz of rotation which gives N THE face of the considerable literature, at times sufficient practice i n laboratory technic to insure the gain- I amounting almost to a flood, which has developed ing of manipulative skill for each student, yet commands in recent years on the subject of the relative value

of the lecture demonstration and the individual labora- tory method in science,' and dating back a t least to 1918,2 i t would appear that there should be consider- able hesitancy in adding to the total. There need be a t any rate no doubt as to the issues involved, since the holding by the American Chemical Society of the symposium on the subject a t its New York meeting in 1935.5 The reasons for the continuance of the debate seem to be on the one hand based on the claims by the proponents of the demonstration method of a greater cost in time and money and greater administra- tive difficulty of the laboratory method, when viewed in the light of the apparent fact that tests prove the educational results to be no better, and perhaps not so good; whereas the opposition clings to a "not proven" verdict and cites the accepted values of learning by doing, the acquisition of operative technics and first- hand understanding of scientific phenomena.

But neither in the reports of the New York sym- posium, nor in the literature referred to, does there appear to be suggested a procedure which is eminently practical and which seems to combine the salient ad- vantages of both the laboratory and of the demon- stration method while lacking many of the disad- vantages of each. Two methods which have been described' and which appear to be most nearly like the one now to be considered, prove on comparison to be clearly different in several particulars. The present approach, developed by the writer while teaching science in a California high school, has now been in use for several years in that and neighboring schools; and furthermore i t has met with an enthusiastic recep- tion when introduced into college courses for the train- ing of teachers of science, conducted by the writer for the past few years.

It is quite likely that the method would not have originated in just the way it did, and certainly not a t the time it did, had i t not been for that great calamity, the Long Beach earthquake, which disrupted so many educational programs in California. As a result of that cataclysm and the general exodus which was soon thereafter ordered by school boards from buildings considered unsafe for occupancy, this particular science teacher found himself evicted almost overnight from his department headquarters, consisting of separate and well-equipped laboratories for chemistry and physics, with an additional lecture room, and presented in their place with a one-room shack fifteen by twenty- -

four feet; the furniture consisting of chairs and a half-dozen deal tables, one kitchen sink fastened to the wall, and ademonstration table nearby supplied with one gas jet, and nothing else. Here surely the obvious thing to do was to apply the lecture-demonstration technic, and, furthermore, no one could rightfully complain if the results were somewhat unsatisfactory, in view of the handicaps. But as a result of a feeling that per- haps some other alternative was worthy of a trial, a compromise was attempted which soon developed into a permanent and highly satisfactory program.

Using the subject of chemistry for the purpose of illustration, the procedure in brief is as follows. The class is divided into groups of two pupils each, and they are assigned in order the various experiments appear- ing in the standard manual. At the laboratory period scheduled, the two students undertake full responsi- bility for the performance of the experiment while the remainder of the class watches from seats nearby. The work is carried out just as it would be by the customary laboratory method, except that from time to time the demonstrators comment or make explanations to the observing group as occasion arises. Those watching take notes as if performing the experiment themselves, following the instructions and answering the questions given in the manual. The teacher comments or offers emergency help if the need arises; otherwise he re- mains a silent spectator.

The following laboratory day another group in turn takes charge, the first demonstrator group then join- ing the class of observers. This goes on until everyone has had his turn, when the rotation is repeated, with the result that in an ordinary-sized class of twenty to thirty-five, each student has appeared as demonstrator during the course of the year some five to eight times. It usually occurs that the students appointed come around in advance of the time and make some prepara- tions, or even run through the whole experiment briefly, to insure a successful demonstration the follow- ing period. It is not necessary to urge them to do this, for obvious reasons.

Now what merit has this over the teacher-demon- stration method, or, rather, some may ask, is i t not obviously inferior to that method because of the neces- sarily poorer performance of students? The answer is quite definite and unmistakable in the minds of those who have conducted the work by this plan. First, what of the effect on the observing group? It will be agreed that there is a vital difference between this and

PAYNE, V. F., "The lecture demonstration and individual the '(child-passive" attitude of the student who with laboratory methods compared. I. The literature," J. C ~ E M . E~uc., 9,932-9 (May, 1932); BARGER, T. M., "Effectiveness of varying degrees of watches the the individual laboratory method in science courses," ibid., 12, tion of the teacher. His natural attitude in this case 229-32 (May, 1935).

WILEY, W. H., "An experimental study of methods of teach- is to take i t for granted that the experiment will be

ing high school chemistry," J. Educ. Psychol., 9, 181-98 (Apr., performed and his Own part is the rather 1918). disagreeable task of recording a foregone set of conclu-

KNox, W. W., "The demonstration method of teachingchern- sions, B~~ not so when two of his feuows perform the istry." J. CHEM.EDWC., 13, 166-71 (Apr., 1936); F ~ L E R . R. W., "Demonstrations or individual laboratory work for high schools,- same experiment. Now there is no assumption that ibid., 13, 2624 (June, 1936). all will go well to a predetermined end. Past ex- ' NAsn, H. B. AND M. J. W. P ~ L L I P S , "A study of the relative value of three methods of teaching chemistry," J. Educ. Research, perience8 perhaps his Own Iecent 15, 371-9 (May, 1027); BARGER, T. M., op. cit. warns him that a t any time something may go wrong or

a mistake may be made; and whether from a Roman Forum complex or from a natural desire partly to justify his own previous failings, there is a sustained alertness which makes both for more careful work on the part of the experimenters, and a better retention of the points involved in the experiments, on the part of the watchers.

And what of the demonstrating team? Here can be seen the greatest advantage of all. Under the cir- cumstances described there is little opportunity for "sloppy" performance, the asking of one's neighbor what the proper result was: "Oh, it's red is i t? I thought it was green, but maybe my test-tube was dirty. Did Mary get red? Well, we'll put it down red." A constant check is operating against that care- less technic which so frequently in the usual crowded laboratory class escapes the watchful eye of even the most diligent of teachers. In addition to the stimulus of teacher watching, we have the far greater stimulus of class observation. Here no fudging goes; without

any teacher encouragement, the class is alert to detect the slightest departure from correct work. Those teachers who have tried it out feel confident that the opportunity for skill in technic under the strong im- press of the conditions is equal to that acquired over a much longer period of standard laboratory prac- tice.

Thus we seem to have all the advantages of economy of time and material which are offered as a chief argu- ment for the lecture-demonstration method, compared with most of the end results of the laboratory method, including certain apparent points of superiority. At least it should justify a trial on the part of those who are investigating this field. Furthermore, when used in teacher training courses, there is no necessity for the development of a new technic to meet standard high- school conditions, a point to be considered when mak- ing comparison with other laboratory substitute proposals. I t may be that out of an emergency, some- thing worthy of perpetuating has arisen.