Background: An evolving literature demonstrates that physical activity in the classroom represents a promising avenue not only for increasing the physical activity of youth but also for facilitating academic achievement and classroom engagement. However, structured physical activity programs that make clear connections with the academic standards across different grades are limited. Objective: The purpose of this study was to examine the feasibility and effectiveness of the "Walkabouts", a web-based physically active learning program, on attention and behavioral control of children. Method: Twelve preK to 2nd grade classes (N = 245 students) were assigned to the intervention (integrating "Walkabouts" with academics) or control (no added movement) group. Teacher ratings of students' attention and behavioral control in the classroom were collected before and after the 7-week intervention in both groups. Treatment fidelity was monitored through observations and daily teacher logs. Results: Teachers perceived the Walkabouts to be feasible, physically active, of appropriate difficulty, and enjoyable for the students. MANOVAs showed a significant time by group interaction, meaning that the intervention group improved significantly more, compared to the control group, in both attention and behavioral control whereas the control group declined over time. A significant time by group by grade interaction showed that the benefit of Walkabouts was larger for the Kindergarten students. Conclusions: Integrating movement with academic subjects with programs such as the Walkabouts, may facilitate learning and academic achievement by increasing cognitive and behavioral control in the classroom. Schools can focus on academic achievement goals without sacrificing physical activity throughout the school day.