This chapter describes school recess which is considered to be the non-curriculum time regularly allocated by schools between lessons for children and adolescents to engage in discretionary leisure activities. It is acknowledged that in recent years, schools have begun to offer structured recess periods where games and activities are organized and led by facilitators. The chapter includes debates currently exist as to whether such approaches can be truly considered recess given the general lack of truly discretionary activities, but literature concerning structured recess for information. Arguably the main intervention approach implemented within recess settings to date is physical changes to the playground environment, which typically involve the introduction of multicolor playground markings. When evaluating the effects of an intervention, it is useful to know how, why, and for which population group the intervention worked. Such information is critical for identifying who and what to target in future physical activity interventions.