In spite of the well-published health benefits of participation in regular physical activity, American children continue to be less physically active than a decade ago, while the number of overweight and obese youngsters continue to rise. A few interventions, CATCH and SPARK for example, have been moderately successful in reversing this trend. Virtually no studies, however, have employed recent Internet technology innovations in attempting to impact youngsters’ knowledge, attitudes and behavior related to physical activity. One of these advances, popularly known as Web-based electronic learning, or e-Learning, has the potential to inform youngsters about the important benefits of physical activity during normally sedentary classroom time. This abstract reports the result of one such study. Elliott (1997) designed and developed the e-Learning module entitled Healthy Hearts to encourage healthy lifestyle decisions in children. The purpose of this study was to evaluate the effects Healthy Hearts had on the physical activity knowledge, attitudes, and behavior of fifth grade children. A 2x2x3 repeated measures design was employed to measure Healthy Hearts effects on, and retention of, physical activity knowledge, attitudes, and behavior of 233 fifth grade boys and girls from 14 West Virginia classrooms. The questionnaire used for this study included three attitude items and a Weekly Activity Checklist adapted from SPARK, and six criterion referenced knowledge items developed from Healthy Hearts objectives. Classroom teachers administered the baseline test before students began using Healthy Hearts. For five weeks following the baseline test, Group 1 engaged in Healthy Hearts lessons by going to a computer lab for approximately 45 minutes twice a week while Group 2 participated in regularly scheduled classroom activities. After Group 1 finished Healthy Hearts, both groups completed Test 1 and then teachers from Group 2 implemented Healthy Hearts with their classes. When Group 2 finished using Healthy Hearts, both groups completed Test 2. Repeated measures ANOVA (alpha=.05) revealed significant effects of Healthy Hearts on physical activity knowledge and attitude, and significant knowledge retention, however, Healthy Hearts had no effects on behavior. Results of this study suggest Healthy Hearts could be an effective component of a coordinated school health program. There is a need for further design, development, and evaluation of Healthy Hearts and similar e-Learning interventions designed to increase the physical activity of American youth.Keyword(s): curriculum development, physical activity, technology