The subjects were 411 institutionalized adolescent males aged 12 to 15 who were committed as adjudicated delinquents to a State department of corrections. Every male committed during a 1- year period who completed the classification process was included in the sample. The subjects ranged in age from 11 years 7 months to 16 years 4 months. Fifty-two percent were white, and 49 percent were African-American. The sample consisted of 3.6 percent status offenders, and the remaining 96.4 percent were classified as delinquent offenders. The components of the academic/intellectual assessment included the Culture Fair Intelligence Test, the Peabody Picture Vocabulary Test-Revised, the California Achievement Test, and the Wide Range Achievement Test. The findings show that the average scores were considerably below that which would be expected on the average in the general population of adolescents in this age range. Generally, their average scores were one standard deviation below that of the general population, which is considered to be statistically significant. Group averages do not tell the entire story, however. There was considerable variation among the delinquents; some were more deficient than others. Furthermore, delinquents might score poorly in terms of academic achievement for different reasons. For some, poor academic achievement could be explained by lower intellectual ability; for others, however, academic achievement was below what would be expected given their intellectual ability. Possible learning disabilities could be involved for this group, since learning disability is manifested by academic achievement significantly below intellectual ability. Other explanations are also possible, however. Implications are drawn for academic programs for institutionalized offenders and for further research. 4 tables and 29 references