This Research Note compares the performances of 71 primary schoolchildren carrying out curricular tasks in outdoor and indoor classroom settings. By observing, recording and analysing how the children performed in group activities taken from the Scottish curriculum, an evaluation could be made of the relative merits of indoor and outdoor learning. In general, the results show that the outdoors environment had a more positive impact on individual and group performance than the indoor classroom. The effect of the outdoor setting on underachieving pupils was particularly notable, improving their engagement, contribution and self-confidence to match that of their peers. The results also indicate that the indoor classroom setting was less motivating, especially for those children with learning difficulties. By contrast, the richness of the outdoor setting provided an equitable learning environment where both younger and older children thrived, not only as a place where they were able to think creatively and work independently, but one where they could also learn how to collaborate and effectively solve problems with others in their groups. Furthermore, it helped them develop an appreciation of their own abilities and the natural world around them. Therefore, increasing the use of outdoor learning through national policy-making will support cognitive and social development in primary schoolchildren, and help close the attainment gap in Scottish education.