Patterns of early cognitive development among boys in four subcultural groups created by Vernon C. Hall and Daniel B. Kaye

600 boys divided by age (6, 7, and 8 yrs), race (Black and White), and social class (middle and lower) were given tests of memory (free recall and digit span), intelligence (Peabody Picture Vocabulary Test and Raven Coloured Progressive Matrices), learning (paired-associates and a matrices training task), and transfer (paired-associates and pre- and postmatrices test). There were (a) significant age advances for all groups on all measures, (b) social class differences on learning and intelligence tests, and (c) racial differences on intelligence, digit span, and paired-associate learning. All groups transferred in a similar manner. Factor patterns across age included more similarities (including similar developmental changes) for the different groups than were expected.