Classroom-based physical activity is a new approach aiming to improve both physical activity levels and academic achievement. This study investigated the acute effect of a 10-min bout of aerobic physical activity integrated with math practice, compared with a seated math practice, on executive function and enjoyment among normal-weight (n = 24) and overweight children (n = 11). Thirty-five typically developing prepubescent children (10.55 ± 0.74 years) completed a session of physical activity integrated with math practice and a seated math practice session in counterbalanced order. Results showed that following integrated physical activity, the response time in the Standard Flanker improved more than after seated practice. Among the overweight children, physical activity benefitted performance in the Standard Flanker by preventing the decline associated with seated practice. Children enjoyed the physical activity practice more than the seated practice. These findings suggest that integrating physical activity with academic instruction may be a realistic strategy for promoting physical activity because it may facilitate, not antagonize, executive function.