Physical education should prepare students to participate in physical activity for a lifetime. Unfortunately, many adults are sedentary, while others regularly drop out and back in to physical activity in response to life events. This article summarizes research examining adolescent profiles that predict who is more or less likely to participate in physical activity after graduation. One of the most reliable predictors for lifelong physical activity appears to be the power of early physical activity experiences to shape future attitudes and expectations toward physical activity. This information can inform professionals' understanding about physical education content and teaching strategies to increase students' skillfulness, knowledge, perceived competence, and enjoyment in physical education, which may lead to lifetime physical activity choices when they are on their own.