This paper, organized into three sections, describes the development, implementation, and supervisory aspects of a cooperative learning program in a typical fifth-grade classroom. Discussed from the teacher's point of view, section 1 addresses: (1) development of teams; (2) social skills development; (3) teammate interdependence, heterogeneous teams, team interdependence, accountability, and activity appropriateness--five essential concepts which must be built into a successful cooperative learning lesson; and (4) classroom applications. Section 2 details the training, orientation, and experiences of a student teacher with respect to cooperative learning methods in three fifth-grade classrooms. This section describes a research project designed to evaluate the five essential components of cooperative learning lessons through classroom observation, conferences with students and teachers, and surveys administered to both teachers and students. Results suggest that cooperative learning is an effective technique for successful teaching and learning. Apendices contain a student teacher questionnaire, the evaluation instrument, and cooperative learning questionnaires for teachers and students. (LL)