Maintains that current research suggests that heterogeneous grouping is preferable. Reports on a study of a new mathematics curriculum using 600 students in 6 Dutch schools. Finds that students in heterogeneous classes taught with cooperative-learning techniques achieved more than students in traditional ability-grouped classrooms. (CFR)

Presents study results on the effects of students working in pairs on spelling in three different grades. Explains that students working individually were compared to students working in pairs. Reports less off-task behavior for the younger students working in pairs. Concludes that effort increases in pair work, but achievement increased only at…