The purpose of this study was to examine the contribution of quality physical education (QPET) in a Comprehensive School Physical Activity Program (CSPAP) which is intended to promote physical activity (PA) behaviors in and outside of schools. Participants were nine elementary physical education teachers and their fourth- and fifth-grade students (n = 1111) in year one, n = 1012 in year 2). The student’s daily PA minutes were assessed using a 7-day PA log. The PE teachers’ levels of QPET were assessed by coding 63 videotaped lessons (Mlessons/teacher = 7.03, SD = .74) using the Assessing Quality Teaching rubrics (AQTR), which consisted of four essential dimensions including Task Design, Task Presentation, Class Management, and Instructional Response. Codes were confirmed through interrater reliability (82.4%, 84.5%, 94%). Data were analyzed through descriptive statistics, bivariate correlations, multiple R-squared regression models, and independent sample t tests. The results indicated that the overall QPET practices (R = .126, R2 = .02, F = 32.387, Sig.= .000, P < .01) and all four essential dimensions (R = .127, R2 = .02, F = 8.560, Sig.= .000, P < .01) were significant contributors to students’ student daily PA behaviors. These predictors were significantly higher in girls (R = .157, R2 = .03, F = 6.15, Sig.= .000, P < .01) than boys (R = .113, R2 = .01, F = 3.57, Sig.= .007, P < .01). The Instructional Response was a significant predictor of PA among girls (β = .12, t = 2,068, Sig. = .039, P < .05 level), but not boys. Further, students’ who experienced high QPET were significantly more physically active than those students who did not have this experience (t = 4.334, df = 2089, Sig. = .000, P < .01). It was concluded that the QPET practices played a critical role in promoting students’ daily PA engagement in and outside of schools.