Leisure-time physical activity (PA) patterns of adolescent boys and girls were studied. Data were collected from 1000 children in grades 9 through 12 using a self-report questionnaire administered in physical education classes. Depending on age and gender, 10% to 25% of youth report being completely sedentary. Contrary to the findings of most national-scope studies, there was little difference in the extent of participation in PA for boys and girls. Overall, approximately 60% of boys and 56% of girls report participating in PA 3 or more days per week for 30 minutes or more per occasion, far short of the national health goal of 75%. Findings also reveal that participation in leisure-time PA declines substantially with age