Background: Decreasing the risk of overweight and obesity from an early age is imperative and efforts should focus on fostering children's physical activity (PA). Within school-based interventions, there is insufficient evidence on the effectiveness of the use of character peer-modeling and goal setting to increase physical activity. Therefore, the purpose of this study was to examine the impact of a school-based intervention on PA and enjoyment of PA in grades 3-5 elementary school age children at two urban elementary schools. Methods: Participants were 95 students of 8-10 years old; activity monitors were used to assess physical activity. Daily physical activity and enjoyment was recorded at baseline, intervention, and at a 6-school-week follow-up. Results: PA significantly increased in the intervention school averaging 5549 steps at base-line, 5889 steps during the intervention, and 6515 during follow-up (p <0.05). Participants significantly increased their moderate to vigorous physical activity from 28.54 min at baseline to 30.06 minutes at week 4 and 36.45 during follow-up (p <0.05). There was no change in enjoyment levels from baseline to follow-up. Conclusion: The Fit "n" Cool Kids intervention presents the potential of peer-modeling and goal setting for increasing PA at school. Continued interventions in schools may positively influence children's healthy living patterns.