This study compared the physical and psychological effects of running to those of the normal physical education program of activities among 154 fourth, fifth, and sixth graders who were randomly assigned to conditions within a true experimental design. The running program consisted of three 30-min sessions per week for 12 weeks in lieu of attendance in regular physical education classes. Findings showed that although boys tended to run faster than girls overall and that older children run faster than younger children, running-program participants performed better on an 800-m run, had lower pulse rates, and performed better on a test of creativity than did regular physical education participants. Running boys had less body fat, and running girls had more creative involvement in class. No differences were found on 50-m dash performance or perceptual skill. On total behavior, girls were more self-controlled than boys, and self-concept tended to become less positive with increased grade level. Running performance for 800 m persisted for 5 months among boys in the treatment, but not among girls. Running was judged effective for enhancing the cardiorespiratory health and creativity of school children.