Background: Primary and secondary school ages have been considered key moments to address the decrease of moderate-tovigorous physical activity (MVPA). Individual (eg, age, gender, and weight status) and contextual factors (moments of the day) need to be considered for a better explanation of the phenomenon. The quantity and quality of physical activity in Physical Education (PE), school recess (SR), and after school (AS) time need to be taken into account to solve the low levels of MVPA in youth. Methods: A sample of adolescents (N = 231, 14.6 ± 1.2 years old) was studied using accelerometry to determine the objective MVPA level in PE, SR, and AS. Results: Results indicated statistically significant differences on MVPA between contexts (AS > PE > SR, P < .001) as well as regarding the individual factors: age (older > younger in PE and younger > older in SR time; P < .001), gender (boys > girls in all contexts, P < .001), and weight status (overweight > nonoverweight in AS, P < .01). Conclusions: Because students did not meet the daily MVPA recommendations, some strategies have been provided in each of the contexts analyzed.