AbstractRaw scores on the 16 K‐ABC subtests and the total raw scores on the sequential and simultaneous processing scales and the achievement scale were correlated with age in months for two separate samples, each subdivided by race and sex: the K‐ABC standardization sample (N= 2000) and an additional group of blacks and whites tested during the development of the K‐ABC sociocultural norms (N= 615). Within each sample, the highest and lowest correlations from all race/sex groups were contrasted across all K‐ABC subtests and scales. All correlations between age and raw scores were statistically significant (p⩽ .05). No significant differences occurred in the magnitude of these relationships as a function of race/sex grouping, supporting the construct validity of the K‐ABC as a developmental measure of children's aptitude and achievement for blacks, whites, Hispanics, males,