This paper views delinquent behavior as a defense against low self-esteem brought about by poor performance in school. Defensiveness is operationalized as a discrepancy between scores on measures of conscious self-esteem (high) and unconscious esteem (low). A representative national sample of 720 boys was divided into two age groups: 11–14 years, 15–18 years. Among the older group, successive interaction hypotheses predicting increasing levels of delinquent behavior were supported. The result was a predicted high delinquency defensive group whose mean delinquency score was at the 86th percentile of the population distribution. The hypotheses were not supported in the younger age group. Differences in accumulated social experience in school are suggested as accounting for the difference between age groups.