This synthesis offers a descriptive inventory of research studies of cooperative learning at the secondary level. While cooperative learning techniques vary, they all share an interest in finding an alternative to "frontal teaching"--the teacher instructing the whole class or individual seatwork by students. Cooperative methods allow students to work in small groups under the assumption that cooperative tasks are more likely to motivate students to learn and provide more individual help for students. Cooperative learning is also advocated for improving social relations between races, ethnic groups, high and low achievers, or for increasing productivity in problem solving. A summary is presented on studies of five major techniques for implementing cooperative learning in grades 7-12. Twenty-seven reports of high quality studies were reviewed, involving 37 comparisons of cooperative versus control methods. The effectiveness of cooperative learning is discussed along with implications for practice. Data collected in the studies are presented on 10 pages of tables and a list of 56 references is included. (JD)