School modernization efforts can make considerable improvements to the quality of the indoor environment, which can thereby influence building occupants’ health, satisfaction, and performance. We found that current modernization strategies are bettering thermal comfort conditions by stabilizing temperatures within the comfort zone, improving air quality by reducing particulate matter, decreasing background noise levels typically caused by mechanical equipment, and increasing daylight distribution and exposure to natural light. Modernization was also found to result in higher satisfaction ratings of the educational environment among teachers and students alike, suggesting that even though Indoor Environmental Quality factors may be “invisible” to building occupants, they have a tangible impact.