The major objection to a program of this type is that it is sometimes extremely difficult and, in the early years, often quite impossible to decide whether the child is really defective or is merely slow in development. Some children come to their normal powers slowly, but ultimately reach a level of intellectual and physical efficiency so high that they are not to be classed with the defectives. One hesitates, therefore, to give up the teaching of reading in the case of a particular child until all possibility of his development is past. It is better to err on the side of too great training than to despair at too early a date.
Tests of General Intelligence
In the effort to discover defectives various systems of tests have been devised. The general assumption back of all these systems is that a defective child is one whose mental development has prematurely ceased. For example, a twelve-year-old child may be behind in his development to such an extent that he has a mind like a four-year-old. If, now, it can be determined what mental powers are possessed by an ordinary four-year-old and if the defective can be shown to possess the same powers, and no more, it is possible to adapt instruction to his real intellectual needs. Technical students of the problem have accordingly drawn the distinction between physiological age and mental age. In the example cited above the physiological age is twelve; the mental age, four.
A system of tests of this kind has another use. If a child is put through the tests at intervals of a year, it can be ascertained whether he is improving or standing still. In this way some of the uncertainties as to the permanence or temporary character of his deficiencies can be removed.
Tests of the type under discussion are called tests of general intelligence. An example taken from one of the most widely used systems, namely, the Binet-Simon series, will serve to show what the tests are and how they are used. The special form of the test here quoted is that worked out by Professor Terman. His exposition of one of the fifth-year tests is as follows:
Materials. It is necessary to have two weights, identical in shape, size, and appearance, weighing respectively 3 and 15 grams. If manufactured weights are not at hand, it is easy to make satisfactory substitutes by taking stiff cardboard pill-boxes, about 1¼ inches in diameter, and filling them with cotton and shot to the desired weight. The shot must be embedded in the center of the cotton so as to prevent rattling. After the box has been loaded to the exact weight, the lid should be glued on firmly. If one does not have access to laboratory scales, it is always possible to secure the help of a druggist in the rather delicate task of weighing the boxes accurately. A set of pill-box weights will last through hundreds of tests, if handled carefully, but they will not stand rough usage. The manufactured blocks are more durable, and so more satisfactory in the long run. If the weights are not at hand, the alternative test may be substituted.
Procedure. Place the 3-and 15-gram weights on the table before the child some two or three inches apart. Say: “You see these blocks. They look just alike, but one of them is heavy and one is light. Try them and tell me which one is heavier.” If the child does not respond, repeat the instructions, saying this time, “Tell me which one is the heaviest.” (Many American children have heard only the superlative form of the adjective used in the comparison of two objects.)
Sometimes the child merely points to one of the boxes or picks up one at random and hands it to the examiner, thinking he is asked to guess which is heaviest. We then say: “No, that is not the way. You must take the boxes in your hands and try them, like this” (illustrating by lifting with one hand, first one box and then the other, a few inches from the table). Most children of 5 years are then able to make the comparison correctly. Very young subjects, however, or older ones who are retarded, sometimes adopt the rather questionable method of lifting both weights in the same hand at once. This is always an unfavorable sign, especially if one of the blocks is placed in the hand on top of the other block.
After the first trial the weights are shuffled and again presented for comparison as before, this time with the positions reversed. The third trial follows with the blocks in the same position as in the first trial. Some children have a tendency to stereotyped behavior, which in this test shows itself by choosing always the block on a certain side. Hence the necessity of alternating the positions. Reserve commendation until all three trials have been given.
Scoring. The test is passed if two of the three comparisons are correct. If there is reason to suspect that the successful responses were due to lucky guesses, the test should be entirely repeated.
Remarks. This test is decidedly more difficult than that of comparing lines. It is doubtful, however, if we can regard the difference as one due primarily to the relative difficulty of visual discrimination and muscular discrimination. In fact, the test with weights hardly taxes sensory discrimination at all when used with children of 5-year intelligence. Success depends, in the first place, on the ability to understand the instructions; and in the second place, on the power to hold the instructions in mind long enough to guide the process of making the comparison. The test presupposes, in elementary form, a power which is operative in all the higher independent processes of thought, the power to neglect the manifold distractions of irrelevant sensations and ideas and to drive direct toward a goal. Here the goal is furnished by the instruction, “Try them and see which is heavier.” This must be held firmly enough in mind to control the steps necessary for making the comparison. Ideas of piling the blocks on top of one another, throwing them, etc., must be inhibited. Sometimes the low-grade imbecile starts off in a very promising way, then apparently forgets the instructions (loses sight of the goal), and begins to play with the boxes in a random way. His mental processes are not consecutive, stable, or controlled. He is blown about at the mercy of every gust of momentary interest.
There is very general agreement in the assignment of this test to year V.[57]
Exceptionally Bright Pupils
Thus far the discussion has been of inferior individuals. There are likewise individuals who are superior to the average. Schools have ordinarily taken little account of these. They do not constitute urgent problems in the same sense as defectives. The supernormal child can get his lessons, if he will, so that the teacher will never have to bother with him. A moment’s thought on the matter, however, will convince anyone that society has more to gain from a proper system of training supernormal children than from special provisions for the subnormal. Since defense is of the most vital importance, we may say that society had at the outset to defend itself against the harm that might be done by subnormals. But defense having been provided in adequate degree, attention should turn to the possibilities of great benefit which may be expected from special training of the unusually bright.
Various devices have been suggested for the treatment of the supernormal. In general, the principles underlying these suggestions are the same as the principles for the treatment of subnormals. Separate the unusually bright and give them a type of training which will best develop their personal powers.