RESULTS INDICATE THAT THE DEGREE OF LIKING AMONG ELEMENTARY SCHOOL CHILDREN (DEGREE OF GROUP COHESIVENESS) HAS A SIGNIFICANT INFLUENCE ON ASPECTS OF PUPIL BEHAVIOR. IN THE THEORETICAL FRAMEWORK OF REINFORCEMENT LEARNING THEORY, INVESTIGATION OF RELATIONSHIPS BETWEEN COHESIVENESS (A GROUP VARIABLE) AND INDIVIDUAL BEHAVIOR CAN LEAD BOTH TO A BETTER GENERAL UNDERSTANDING OF GROUP PROCESSES AND TO THE ACHIEVEMENT OF TEACHING GOALS BY THE CLASSROOM TEACHER. A POSITIVE RELATIONSHIP WAS FOUND BETWEEN LEARNING AND COHESIVENESS FOR HIGH BUT NOT FOR LOW IQ STUDENT GROUPS. NO RELATIONSHIP WAS FOUND BETWEEN COHESIVENESS AND TASK PERSISTENCE. IT WAS FOUND THAT THE GREATER THE COHESIVENESS, THE MORE WILL INDIVIDUALS WITHIN THE GROUP ADHERE TO COMMON STANDARDS. FINALLY, IT WAS DEMONSTRATED, BUT NOT UNEQUIVOCALLY, THAT, IN A SIMULATED CLASSROOM SETTING, POSITIVE ATTITUDES OF PUPILS TOWARD ONE ANOTHER ARE POSITIVELY RELATED TO THEIR RECEIPT OF REWARD WITHIN THAT SETTING AND WITHIN ONE ANOTHER'S PRESENCE.