Summary The effects of cooperative and individualistic learning experiences were compared on achievement of academically handicapped, normal-progress, and gifted sixth-grade students. Fifty-five students were assigned to conditions on a stratified random basis controlling for ability and sex. They participated in one instructional unit for 65 minutes a day for five instructional days. The results indicate that cooperative learning experiences promoted higher achievement, greater retention, more positive attitudes among students, and higher self-esteem than did individualistic learning experiences.