Inactivity is associated with many adverse health conditions including: obesity, heart disease, diabetes, and high blood pressure. Understanding adolescent motives to exercise, and the reasons they do not exercise may help to address this national crisis. The research involved distributing an anonymous questionnaire to adolescents (N=140) enrolled in a public middle school in a suburb of a large, Midwest city. Subsequently, we analyzed responses concerning students' exercise behaviors and motivations. This study evaluated adolescents (aged 10-14): (a) exercise habits, (b) sedentary habits, (c) motivation to exercise, and (d) barriers to exercise. Analysis was done using the Mann-Whitney-U Test, using their activity status (inactive or active) to discriminate among the two groups. The self-report questionnaires revealed that as anticipated there were a large number (56.1%) of active adolescents (defined as individuals who engaged in 60+ minutes of moderate to vigorous physical activity four or more days per week) in the sample. Active students were more likely to participate in: (a) team sports (p<.01), (b) unorganized physical activity (p<.04), and (c) exercise outdoors (p<.01) than inactive adolescents. Sedentary activities such as TV watching, using computers, playing video games, and socializing showed no significant difference between the active and inactive groups. Of the 16 listed reasons to exercise, only “for a challenge” was statistically significant (p<.01) when comparing the active and inactive groups. Among the barriers listed: (a) not liking exercise (p<.01), (b)TV (p<.05), (c) being too tired (p<.02), and (d) preferring other activities (p<.01) were found to be significantly different between the active and inactive groups, respectively. The most important reasons to exercise among the sample population were “to get stronger,” “to stay in shape,” “for fun,” and “because it's good for you.” Additionally, students' reasons to exercise were fairly consistent across the population regardless of activity level. The most common barrier to exercise was “homework/schoolwork”. Perceptions of barriers to exercise showed that inactive youth assigned a higher importance to barriers than the active adolescents. Thus, the results appeared to confirm other research findings that adolescents who are more active are less likely to perceive barriers to exercise (and vice versa). Furthermore, the findings have demonstrated that students' involvement in team sports, outdoor activities, and unstructured activities may help them to achieve an active lifestyle.Keyword(s): active participation, exercise/fitness/physical activity, physical education PK-12