Equating intellectual potential in the two groups is most difficult. The results of any intelligence test administered to a young child are of questionable reliability and validity; when the young child is also deaf, these difficulties are multiplied (Levine, 1960; Vernon & Brown, 1964). Every child who applies for admission to the school is given an intelligence test. The one used most often, and uniformly at the present time, is the performance scale of the Wechsler Intelligence Scale for Children. Forty-five pairs are matched within 10 points on IQ test score; 12 pairs show a discrepancy of between 11 and 15 IQ points; 1 pair has a 17-point discrepancy; and another pair has a 20-point discrepancy. The mean IQ score for children of deaf parents is 111.5, whereas the mean IQ score for children of hearing parents is 108.9. Eighty percent of the children with deaf parents have a ‘‘profound’’ hearing impairment (.80 dB in the speech range of the better ear) as do 71% of those with hearing parents (Flower, 1