2021 Yes https://www.mdpi.com/1660-4601/18/2/535 Bikomeye, Jean C Europe North America Observational Students Elementary (K-5) Middle/Jr High (6-8) Stress/Anxiety Green space Nature Schoolyard greening Physical activity Socioemotional health Mental health Child health Experimental design Pre-post study design Health equity Review of 6 experimental studies found schoolyard greening increases physical activity and socioemotional health in children. Findings support greening as an equity intervention for school health promotion.