Only a prolonged trial of special instruction for those presumably behind their proper grade would finally determine how large is this evil of maladjustment. Such an experiment could be satisfactorily carried out only with the co-operation of the board of education. It would mean the employment for some years of expert teachers to train those delinquents found behind their intellectual level in school. Until that time we shall have to take the estimate from psychological tests which indicated that, in our group of serious juvenile delinquents, presumably 29% of those compared had been held back by the school machinery. Since the retardation of these pupils may be attributed to a late start in school life or prolonged absence, the inadequacy of the schools so far as these pupils are concerned may be supposed to lie in their failure to promote pupils quickly up to the school position of their equals. On account of the expense of special teachers such pupils presumably could not be given a chance to make up the school subjects which they had missed and could not be advanced to the grades requiring this knowledge. Whenever this is the case or under any circumstances which keep the pupil behind the school class of his intellectual equals, we have a fundamental cause of distaste for school work. No wonder that such pupils dislike school, become disgruntled and stubborn, run away and rebel at the treatment they receive under the traditional school system. One can hardly blame a self-respecting boy, forced to remain behind his peers, for breaking away from the lock step, playing truant and seeking his education in the streets. The trouble is not with the school authorities alone. They are doing about as well as can be expected with the funds which the people have been willing to provide. The public must be educated up to the recognition of the fact that every child in the school should be allowed to progress as rapidly as his abilities permit. The public schools of Mannheim, Germany, are the great illustration of what can be done to bring the school instruction close to the varying degrees of capacity among the pupils. In the Mannheim schools children may carry from four to eight years of the regular curriculum in eight years, and the brighter pupils may also take additional subjects. The Industrial School in Cleveland has demonstrated that some 14-year-old boys two years backward in school may, with special help, be successfully prepared for high school with about as much likelihood that they will continue the high school course as the ordinary boys (_107_).