Converging evidence suggests moderate to vigorous physical activity (MVPA) has positive effects on cognitive performance. Most specifically bouts of MVPA have been shown to significantly improve cognitive efficiency and response inhibition in children. While these results are consistently observed in laboratory settings, the applications in applied settings remain unclear. This study examined the effects of high intensity exercise, low intensity exercise, and sedentary behavior on response inhibition and classroom on-task behavior following using a repeated measure crossover design. Two one-way ANCOVAs, using number of steps during activity as the covariate, were used to determine if there were any changes to the outcome measures. Results indicate that high intensity activity had a significant effect on successful inhibition of response {F (3, 129) = 3.746, p = 0.013} compared to low intensity and sedentary activity; there were no significant differences in classroom behavior as a result of the activity type {F (3, 147) = 2.544, p = 0.058}. These results provide more evidence that 20 min of MVPA has positive effects on a child’s ability to withhold a behavioral impulse, or respond to a “stop” signal.