By Sofia Postell
The effect of heat waves on schools has become an urgent issue, with news stories on schools closing due to extreme heat becoming more common all over the United States. Schools now have “high temp” days similar to “snow days,” because their ability to deal with hot weather is limited.
A 2020 report found that about half of U.S. schools’ HVAC systems needed updates or significant repairs to appropriately deal with rising temperatures and keep school buildings at a comfortable level. These disruptions have impacts on both teaching and learning, and for math in particular, the impact is noteworthy.
In our recent research brief, my colleagues and I at NWEA investigated whether these increasingly common hot school days negatively impacted test scores. Specifically, we analyzed the effect of the maximum outdoor temperature on math and reading using MAP Growth test scores in grades 3–8, while controlling for background characteristics that may also influence outcomes, such as student’s prior achievement, their race and gender, the state they attended school, and the time of day the test was taken.
We found that higher test-day temperatures, specifically above 80°F, detrimentally impacted math scores, while reading scores didn’t meaningfully change. Although the reasons are unclear, other research has found similar differences in results between math and reading scores.
Our study also analyzed whether there are differences in how lower poverty vs. higher poverty schools experienced the effects of high test-day temperatures on math scores. We found that higher poverty schools experienced up to double the impact of test-day heat than low-poverty schools.
Recommendations for School Leaders
Given the findings, testing on hotter days can have meaningful impacts on student scores. With these results in mind, we recommend the following:
- The ability to mitigate outdoor heat inside schools can be unpredictable. If scheduled testing overlaps with a heat wave, prioritize creating more comfortable testing conditions whenever possible. This can include moving testing locations from warmer to cooler areas within a school.
- Testing students in the morning, before afternoon heat is highest, can also help mitigate these effects.
- Investing in resilient facilities for the long term is critical, ensuring infrastructure planning looks at resource allocations, structural improvements, and upgrades that take educational equity into account.
Our findings show that as temperatures continue to rise, disparities in school facilities—such as having appropriate HVAC systems—can deepen existing inequities and make school infrastructure and building conditions significant issues. While funding sources for building improvements and upgrades are often limited and vary by region, prioritizing temperature controls inside schools is a clear must so students can focus on learning and educators on teaching.
Sofia Postell is a Research Analyst at NWEA.
