The investigation examined the "Wide Range Achievement Test" (WRAT) and its subtests (spelling, reading, and arithmetic), as well as possible differences attributable to the factors of sex, with the "Chicago Non-Verbal" (CNV) as a criterion variable. The 1970 study encompassed 72 Indian students (with a mean chronological age of 13.2 for boys and 13.4 for girls) attending the Riverside Summer Institute at Anadarko, Oklahoma. Test data obtained were examined through mean, standard deviation, standard error, and the Pearson Product Moment. The low correlation between the WRAT and the CNV indicates significant differences; WRAT results show greater retardation than CNV results; WRAT results show a greater variation below the standard mean than is indicated by CNV results; both tests indicate that females are above the mean, and the variation in difference from the mean of the 2 tests is about the same; WRAT scores show the greatest retardation on the arithmetic subtest for both males and females; males show greater deviation below the mean on the reading subtest; and girls show the greatest retardation below the mean on the arithmetic subtest. Cultural factors and tribal differences are cited as limitations to this study. Included with a description of the study and findings are a literature review, a 12-item bibliography, and tables showing mean, standard deviation, and standard error of test scores. (MJB)