The aim of this quasi-experimental intervention study was to investigate the association between primary school students’ (9–13 years) school motivation and regular participation in education outside the classroom (EOtC). School motivation of 311 Danish public students from 24 intervention classes and 88 students from seven parallel comparison classes was measured at the start
and end of the 2014–2015 school year using the Academic Self-Regulation Questionnaire (SRQA). Exposure to EOtC was monitored by intervention and comparison teachers. Multilevel analyses showed that regular exposure to EOtC was associated with improvement in intrinsic motivation and was moderated by prior intrinsic motivation in favor of students with higher prior intrinsic motivation. Results were independent of gender and socio-economic-status.