“…Although few studies have examined the ability composition of training teams using an experimental design, the growing literature on cooperative learning strategies in elementary and secondary education can offer insight into the optimal ability compositions of training teams (see Hooper, 1992;Hooper, Temiyakarn, & Williams, 1993;Webb, Nemer, Chizhik, & Sugrue, 1998). Advocates of mixed-ability groupings claim that, along with its potential positive affective consequences, mixed-ability groupings also have important positive cognitive consequences (Slavin, 1990), especially when tutor-tutee relationships exist among group members (Webb, 1982a(Webb, , 1982b.…”