To prove this, social cognitive skills (i.e. problem solving, self-control, locus of control, and rational attributions) were examined in aggressive and non-aggressive delinquent youths at the two levels of behavioral functioning. Behavioral functioning was defined in terms of the youth's standing in a 10-level behavioral token program. The skills of interest were measured by inventories and questionnaires. On problem-solving skills, a significant interaction was found with higher-functioning, non-aggressive youths doing better than their lower functioning counterparts. Within the aggressive groups, no differences occurred. On the other measures, no differences were noted. The authors suggest that teaching problem solving skills might contribute to a successful program. 6 references, 1 table. (Author abstract modified)