The purpose of this study was to examine the effects of a physical activity intervention package on the self-esteem of pre-adolescent and adolescent females. The package involved three components: physical activity, education and self-report. Subjects (N = 181) were pre-, early-, and middle-adolescent girls ranging in age from 9 to 16 who were enrolled in an independent school. An experimental pre-test/post-test design which involved two independent variables (intervention package and age group), each with three levels, was used. Self-esteem was measured with the Self Description Questionnaire I and II (Marsh, 1988). Results indicated that low self-esteem individuals benefitted from the intervention. However, statistically significant results were limited to the younger age group.