This study evaluated the effectiveness of an innovative, classroom-based physical activity prevention program designed to integrate academic curriculum elements along with a physical activity program in providing moderate-to-vigorous intensity physical activity. A convenience sample of three public school classrooms (one first, third, and fifth grade class) was observed implementing the TAKE 10! program while monitored by either CSA accelerometers or digital pedometers. Pedometer step counts and CSA data were recorded for each student and activity. As calculated from CSA data, average MET levels during the activities were 5.72-7.05 (first grade), 5.51-6.77 (third grade), and 4.98-7.19 (fifth grade), and levels were not different between grades (p > 0.05). Average caloric expenditure (Kcal) per 10-minute session was 25.6-27.8 (first grade), 27.6-33.9 (third grade), and 29.7-42.9 (fifth grade). Measured pedometer step counts per session ranged from 644-931 in first grade, 659-1,376 in third grade, and 1,002-1,041 in fifth grade. TAKE 10! sessions for all three grades produced exercise levels in the moderate intensity range throughout full duration of the session. Classroom-based physical activity promotion provides a useful strategy to promote meaningful physical activity among school children.