The self-serving effect (SSE), often depicted as a bias, is the tendency to accept responsibility for one's own successes but not one's own failures. Two studies of Australian fifth graders (n=226, n=559) were further analyzed to investigate individual differences in SSE. The Sydney Attribution Scale measured students' perceptions of the causes of their academic successes and failures. The Self Description Questionnaire measured four nonacademic and three academic self-concepts. Mathematics and reading achievement data came from standardized tests and teacher ratings. Results from these studies demonstrate that the size of the SSE for academic attributions varies with the cause being judged, the respondent's achievement level, and the respondent's self-concept. The SSE is larger for attributions to ability and effort attributions than to external causes, it is larger for more able students, and it is larger for students with higher self-concept. Furthermore, SSEs for outcomes in mathematics and reading, particularly for attributions of ability, are content specific. The logical pattern of relations among the SSEs, academic self-concept and achievement, and the content specificity of the SSE, argue that academic achievement and self-concept are nonmotivational influences on the SSE. (Author/BS)