2016 No https://onlinelibrary.wiley.com/doi/10.1111/ina.12241 Mendell, M. J. North America Observational Epidemiology Study Students Elementary (K-5) Ventilation rates Carbon Dioxide (CO2) Test Performance Cognative function Ventilation Schools Learning Achievement Children Indoor air quality Longitudinal study analyzed CO₂-based ventilation rates over two years in 150 classrooms; test score data showed small positive associations between ventilation and English/math outcomes. Findings suggest improving ventilation to current standards may benefit learning and public health policy.