Objective: To examine provider and type variation in social support (SS) for activity. Methods: Three hundred sixty-three fifth to eighth-grade students completed a questionnaire assessing self-reported activity and social support (SS) from 3 providers: mom, dad, and peers. Important covariates of activity were included in the analysis: age, BMI, sex, and maturation. Results: Structural equation modeling indicated peers, transportation, and praise affected activity levels. Boys reported greater SS than girls did. Maturation, age, and BMI exhibited unique affects on SS. Conclusions: Increasing positive feedback, transportation to places to be active, and peer support may prove advantageous in improving activity levels in this age-group.