Short Circuits or Superconductors? Effects of Group Composition on High-Achieving Students’ Science Assessment Performance

Although many cooperative learning methods advocate grouping students heterogeneously in order to maximize the diversity of perspectives, skills, and backgrounds, past research shows that heterogeneous grouping generally ben-efits low-ability students but does not necessarily benefit high-ability students. This study investigates the effects of group ability composition (homogeneous versus heterogeneous) on group processes and outcomes for high-ability students completing science performance assessments. High-ability students working in homogeneous groups uniformly performed well, and high-ability students in some heterogeneous groups performed as well as high-ability students in homogeneous groups; but high-ability students in other heterogeneous groups did not perform as well. The quality of group functioning served as the strongest predictor of high-ability students’ performance and explained much of the effect of group composition.