A cost-benefit analysis based on existing green schoolyards in California compared a green schoolyard prototype with a gray schoolyard prototype. Over a 20-year period, the green schoolyard's cumulative net cost was 381% less than the gray schoolyard. The prototypical green schoolyard would yield at least $600,000 in net benefits related to increased student attendance, increased academic performance, increased staff retention, and savings in building heating and cooling costs (breaking even at 9 years), while the gray schoolyard would yield no benefits over time.
Trust for Public Land and MKThink. (2022). “California Green Schoolyards: A Cost-Benefit Study.” https://www.tpl.org/sites/default/files/220511_TPL_GSY_Report_Final.pdf.