Cooperative learning is a generic name that refers to several methods for the organization and conduct of classroom instruction. These methods include Complex Instruction, Group Investigation, Jigsaw, Learning Together, STAD, and others (Cohen, 1986; Johnson & Johnson,1987; Sharan, 1980; Sharan & Sharan, 1992a; Slavin, 1990). A number of authors have written about the similarities and differences between the various methods (Kagan, 1985; Knight & Bohlmeyer, 1990; Sharan, 1980; Slavin, 1990). As the name implies, cooperation among students during the process of learning is one fundamental feature common to all the methods. Peer cooperation is facilitated by organizing students into small groups, usually numbering between three and six, within the classroom. The small group serves as the social unit in which learning takes place through peer interaction and communication, as well as through individual study. A classroom can have as many as eight or more groups that function simultaneously. Group-centered cooperative learning provides teachers with a flexible instructional technology that allows students to study at different rates; cultivate divergent interests; produce different academic products not always predetermined by the teacher; not be subject to a lock-step uniformity in pace and content of

learning; to engage in unmediated communication with peers as part of the process of learning; and to give and receive ideas, clarification, and assistance.