Academic achievement of peer group leaders and members: Contributions to adolescents' social, school, and psychological adjustment.

This one-year longitudinal study examined how the academic achievement of peer group leaders and nonleader members was associated with individual social, school, and psychological adjustment in Chinese adolescents. Participants included 2450 middle-school students (1233 boys; initial Mage = 13.96 years) in China. Data were collected from multiple sources, including self-reports, peer nominations, teacher ratings, and school records. Peer groups and their leaders were identified using the WalkTrap community detection algorithm, resulting in 256 peer group leaders across 238 peer groups. Multilevel modeling revealed that academic achievement of group leaders and nonleader members both positively predicted individual academic achievement and social competence. Whereas group leaders' academic achievement negatively predicted adolescents' aggression and externalizing problems, nonleader members' academic achievement negatively predicted adolescents' peer victimization and internalizing symptoms. The results indicate similar as well as distinct patterns of longitudinal associations of leaders' and nonleader members' academic achievement with individual adjustment in adolescent peer groups. The results suggest that it may be an effective strategy to use peer group-based education and intervention programs involving group leaders and group members to help adolescents develop social and academic competence and reduce externalizing and internalizing problems.