There were two strains, to be fair: there were eugenicist arguments as well, and some authors from the turn of the twentieth century go on at length about how the problem children probably aren't _actually_ gifted because truly superior people wouldn't misbehave. But for example, from "Classroom Problems in the Education of Gifted Children" (1917):

"It is just as important for the bright child to acquire correct habits of work as it is for the dull or average child to do so, whereas in the ordinary class the brightest children are likely to have from a fourth to a half of their time in which to loaf, and never or rarely have the opportunity of knowing what it means to work up to the limit of their powers. The consequent habits of indolence, carelessness and inattention, which are so likely to be formed under such conditions, might be avoided by the provision, for such children, of special courses of such a nature as to fit their peculiar characteristics."