How is environmental greenness related to students' academic performance in English and Mathematics?

Background: Previous studies point out a positive association between academic performance and school surrounding greenness, but the population included in these studies only recruited single-grade students. Objectives: To design a more all-rounded investigation of the association between school surrounding greenness and students' academic performance in general in Massachusetts, USA. Methods: We included a total of 27,493 3rd-10th grade students from public schools over 9 years (2006-2014) in the study. Academic performance (i.e. English and Mathematics achievement level) were primarily based on Composite Performance Index (CPI) as well as the percentage of students who scored Proficient and Higher (AP%) in the examination. Normalized Difference Vegetation Index (NDVI) and green land use area (within 250-2000 m circular buffer) were used to server the index of school surrounding greenness). We applied generalized linear mixed models (GLMMs) to investigate the relationship between surrounding greenness and academic performance with adjustment on socio-economic and demographic factors. Results: We found a significant positive association (p < 0.05) between school surrounding greenness and academic performance based on AP% or CPI, after adjusting for the potential confounders. Higher exposure to green land use area was also significantly associated with increased academic performance. Using different buffer levels did not dramatically change the major findings. The positive relationship between school surrounding greenness and academic performance was consistent across different sub-populations. Conclusions: A higher sin-rounding greenness contributes a better academic performance in students of all grades. This finding could serve as a reference for designing green landscape especially near school areas.