2016 Yes https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4924023/ Bidassey-Manilal, Shalin Africa Observational Epidemiology Study Staff Students Middle/Jr High (6-8) High School (9-12) Temperature Humidity Lighting Vision Headaches Stress/Anxiety Temperature Health School South Africa Climate change A high proportion of students felt tired (97.2%), had low concentration (96.8%) and felt sleepy (94.1%) during at least one hour on any day. There were statistically significant correlations, when controlling for school cluster effect and time of day, between indoor temperatures ≥32 °C and students who felt tired and found it hard to breathe. Consistently higher indoor classroom temperatures were observed in classrooms constructed of prefabricated asbestos sheeting with corrugated iron roof and converted shipping container compared to brick classrooms. Longitudinal studies in multiple seasons and different classroom building types are needed.