“…Six studies collected and analysed data on a solely student level [4,23,27,29,34,35], five studies also included data from teachers, staff and parents [6,30,31,32,33] and one study [5] only included data from parents. Eight studies used interviews [6,27,29,30,31,32,33,34], six studies used questionnaires [5,7,28,30,31], three studies used learning assessments [29,30,31], two studies used observations [32,34] and, in each case, one study used a postal survey [23], written documents [29], drawings and concept maps [34], and accelerometry [4]. The quantity of compulsory educational activities in a natural or cultural environment outside the classroom varied from one school day bi-weekly to a duration of eight weeks [27], and a six-month full week programme [23].…”