Decreased physical activity (PA) influences childhood obesity and student learning. Sixty minutes (min) of daily moderate-to-vigorous physical activity (MVPA) are recommended for good health and optimized academic achievement.

We quantified all-day and in-school PA in association with academic success. Cross-sectional accelerometer data from 1115 second-twelfth graders were evaluated for daily and in-school MVPA and vigorous physical activity (VPA). Associations between PA values and year-end grade point average (GPA) in grades 6–12 and criterion referenced standardized tests in reading (CRT-R) and math (CRT-M) were examined for grades 3–8 and 11 by multivariable regression.

MVPA and VPA declined as student grade level increased. Higher in-school and full-day PA was associated with increased academic success (e.g., GPA and standardized testing), with the effect size increasing with advancing grade level. Accumulating 30 min more of in-school MVPA was associated with 0.63 higher GPA. Accumulating 10 min more of in-school VPA was associated with higher standardized test scores: +11.9% and +12.0% for CRT-M and CRT-R, respectively.

Across advancing grade levels, students were on average less physically active. Habitual physical activity at every grade level was associated with higher levels of academic success based on GPA and standardized test scores in both math and reading.