Attention Deficit Disorder (ADD) symptoms in children are relieved after spending time in nature. The greener the setting, the more the relief. When parents with children with ADD were asked to list the activities that improved their children's behavior, 85% listed green space activities, including fishing and soccer. Only 43% listed indoor activities.
Taylor, Andrea Faber, Frances E. Kuo, and William C. Sullivan. (2001). Coping with ADD: The surprising connection to green play settings. Environment and Behavior, 33(1), 54-77.