The time children spend in nature has severely decreased. While nature-based learning at school is considered an important strategy in addressing this, numerous knowledge gaps continue to remain. To address these, a systematic review was undertaken. Nine commonly used health and education databases were searched from inception to January 2019. To be included, study participants were required to be children aged 4 to 12 without health or developmental conditions with a focus on nature-based learning. The methodological quality of the included studies was assessed, followed by a descriptive synthesis. Out of 4703 results, 20 quantitative studies were included. There was a lack of universal definition of nature-based learning. This resulted in heterogeneity in how interventions were delivered, and outcomes measured. Overall, nature-based learning had varying levels of positive impacts across a range of outcomes. Despite these positive findings, the evidence base is constrained by some methodological issues.