Numerous researchers have argued early adolescent behavior patterns are among the best predictors of later achievement and social-psychological adjustment outcomes. In the current study, a secondary data analysis was conducted to determine the extent to which four prosocial behaviors (cooperation, assertiveness, self-control and prosocial behaviors toward peers) and two forms of aggression (overt and relational) influence academic performance (as indexed by GPA and standardized achievement scores). Additionally, the potential moderating role of two school environment variables (perception of school climate and teacher bonding) were also considered in order to further examine the social-emotional environment of middle schools. Examining concurrent relations between grade 5 social behaviors and academic performance revealed all four forms of prosocial behavior were positively related to higher academic performance. Predictive relations between grade 6 social behaviors and academic outcomes at grade 9 indicated that of the four prosocial behaviors and two forms of aggression, cooperation alone predicted the likelihood of later academic achievement. Finally, it was hypothesized that prosocial behaviors, perception of school climate and teacher bonding would serve as moderators between aggression and academic performance; however, this prediction was unsupported. By drawing attention to the limited typology employed in studying prosocial behavior, as well as the methodological challenges that arise when examining these behaviors during adolescence, the hope is to spur research geared towards a more comprehensive understanding of prosocial development. / Master of Science