The greening of three middle school schoolyards in Austria reduced students’ physiological stress levels and enhanced their psychological well-being. Students perceived the schoolyard to be more restorative following the redesign.
Kelz, Christina, Gary W. Evans, and Kathrin Röderer. (2013). The restorative effects of redesigning the schoolyard: A multi-methodological, quasi-experimental study in rural Austrian middle schools. Environment and Behavior, 47(2), 119-139.