This investigation used social psychological concepts in analysis of social processes among pupils engaged in a cooperative task. It explored several ways of increasing interdependence among participants and determined the effects of such conditions on pupil performance. The subjects were 228 randomly selected fourth and fifth grade students. The subjects were divided into three groups. Each group was given a problem which required cooperative action for its completion. Group performance measures were obtained and related to the group's social interaction which had been recorded by observers in precoded categories. There were five experimental performance conditions: unstructured condition, task requirements, task role, group role, and a combination of task role and group role. The strongest results were sex differences. Girls responded to the role demands created in the different conditions, whereas boys did so minimally. In the unstructured performance conditions, the girls' quality of work was better than the boys'. In comparison with other conditions, however, this condition resulted in the poorest quality of performance for both groups. (Footnotes and a bibliography are included.) (BRB)