This research project explores the effectiveness of Outdoor Learning (OL) on children’s indoor learning (IL) and their learning overall, as well as the differences between learning indoors (ID) and outdoors (OD). The value of OL held by teachers is investigated and discussed alongside the question: Should OL be a mandatory subject within the National Curriculum? A triangulation method is used, comprised by structured observations, questionnaires and an interview. The research found that the main difference in children’s learning OD to ID is the overall engagement. Another finding was the positive attitude teachers had towards OL, however the lack of confidence of the subject as well as the issue of funding makes it difficult to integrate OL into the curriculum. This reason, along with the nature and objectives of OL, contribute toward the consensus that OL should not be a mandatory subject within the National Curriculum, but incorporated into the curriculum where possible and necessary. This research recommends more scrutiny and exploration of ways to include OL into schools, as well as encouraging and raising awareness to professionals to explore options of initiatives such as Nature Premium (2020) to connect more children to nature.