This study explored the impact of peer-reputations for academic ability and affect/liking on academic outcomes in a sample of preadolescents. In light of the popular stereotypes regarding the differential academic abilities of girls and boys (favoring girls in English, and boys in math and science), it was hypothesized that peer-reputations in English would be more predictive of academic outcomes (measured via school-grades and standardized test-scores) for girls than for boys, while math and science reputations would be most predictive of boys’ academic outcomes. Further, it was also hypothesized that these links would be stronger for school-grades than for standardized test-scores. As expected, overall, peer-reputations were found to be predictive of school-grades but not standardized test-scores. Further, the results reveal that although ability reputations in most areas were predictive of grades for both sexes, gender differences were observed which were consistent with hypotheses. Results suggest that children’s peer-reputations may play an important role in their academic achievement, especially within domains most central to their gender identities.