Marks given by a teacher are satisfactory only for a normal child with normal age for the grade. Brilliant children are over-praised for work which, though over the ability for the group, is under their own ability. Marks given to stupid children are misinterpreted by parents so as greatly to prejudice the effort of the child. Though his work may be such as to merit encouragement his mark may be very low. Teachers’ marks are, aside from their inaccuracy, just, only in a group that is perfectly classified; just, only when the children are all of the same ability and all possess the same initial information. So far as they are unjust they are subversive of our aims, as they then transmit a faulty message to the home and disrupt the continuity of school and home education.[5] Such marks as are here advocated would correct this feature of our present system, as well as the inaccuracy of our present marks. It is a mark which evaluates the accomplishment of the child in terms of his own ability. A brilliant child would no longer be praised for work which in terms of his own effort is 70 per cent perfect, in terms of the maximum of the group 90 per cent. The teacher gives him a mark of 90 while we mark him 70. A stupid child who does work which is marked 70 in terms of the maximum of the class but 90 in terms of his own, a limited ability, is no longer discouraged. His effort is evaluated, and the praise which he receives from home is merited and consequently economical, since the resultant satisfaction cements the bonds of concentration and attention. Such a mark is an actual index of the effort that child is making and consequently forms the proper link between the school and the home. Parents would need no great instruction in the interpretation of these marks, since they have always acted as though the other marks were these, and since these also are in percentage form. The only kind of mark they can understand is an Accomplishment Ratio. I found that the parents of the children at Garden City were more attentive to such marks than to others, and acted upon them more readily. Of course the parents of the very intelligent children, who are used to marks above 90, are surprised at first when you tell them that your mark of the child is 80; but upon explanation, which should in all cases precede the first report to the parents, they immediately see the value of such grading. It is fortunate in this connection that the greatest amount of explanation is necessary about intelligent children, as one usually deals then with intelligent parents. THE DERIVATION OF AGE NORMS