The "Run, jump & fun" intervention consists of four 30 minutes sessions per week for one school year. Activities are mostly conducted as whole class activities. Head of schools and teachers/school pedagogues are involved in an initial intervention establishing process, guided by Active School personnel. The aim is to create a local plan for the intervention tailored to the particular school. Examples are "movement band", structured activities during recess with older students (13-15 years olds), etc. Activities are created to be fun, motivating and with moderate to high intensity PA.

This intervention is implemented as PA for 30 min in two Mathematics and two Danish lessons each week for one school year. Activities are conducted at whole-class level.

The physical activities in "Move & Learn" are closely linked to the Mathematic curriculum and the Danish curriculum. The way the body is integrated in the learning task can vary. Examples are bodily or motor-skill demanding activities or less vigorous activities, e.g. standing up miming, using hand gestures or facial expressions. An important aspect of the interventions is that movements should be task relevant. The intervention is developed based on the embodied learning theory.

Control schools will continue their usual practice.

The intervention can be designed e.g. to consist of morning sessions each schoolday (except days with PE) or with different time slots at different weekdays. Activities are mainly conducted by school personnel, but can be supplemented by activity sessions during recess once a week lead by older students. Further, to create variation and inspire teachers, external PA parties, for example instructors from local sports clubs are invited to conduct sessions for the students and deliver teaching materials.

To align with the aim of the Danish school system, activities must have a pedagogical purpose.

Both the "Run, jump & fun" and the "Move & learn" interventions have a set of strategies underpinning implementation (see Move & Learn" for more details).

Both interventions will be grounded in Self-Determination Theory and all activities will be designed to be motivating and enjoyable for all children including those neither particularly fit nor enthusiastic about PA.

Danish National Test System. The tests are computerized and composed in a progressive manner, depending on the individual child's performance, such that correct answers lead to more difficult subsequent questions, and incorrect answers lead to easier subsequent questions. The final test result is therefore based on the level of difficulty, not the number of correct answers. The tests are divided into three different domains; for mathematics: algebra, geometry, and basic mathematics skills. No aids are permitted during the tests. The tests are scored on a scale from 0 to 100 in each domain. For this study, the mean of the three domains will be used for analyses

Hogrefe Psykologisk Forlag. (2014).