Who’s Learning in the Hottest Classrooms? New Bren Research Sheds Light on School Heat Inequity

My interest in extreme heat as an environmental justice issue grew out of earlier collaborative work with my former graduate student Bruce Mitchell at the University of South Florida, who is now a Principal Researcher at the National Community Reinvestment Coalition in Washington, D.C. Together, we documented the uneven racial/ethnic and socioeconomic distribution of urban heat islands across U.S. cities — work that led us to frame “thermal inequity” as an environmental injustice. That research established a clear and disturbing pattern, but it led me to think about a related question: what about children in schools? Schools had received very limited attention in the thermal inequity literature, and more specifically, no national study had quantified how extreme heat exposure varies across schools by race, ethnicity, or income. School-age children, after all, are a captive population — confined to the same location for most of their waking hours during the school year — and that made them a uniquely vulnerable population group that urgently needed more research attention.

The core of the work involved integrating data on nearly 87,000 public schools with five years of daily temperature records from the CDC’s National Environmental Public Health Tracking Network. The geospatial analysis — linking census tract-level temperature data to each school’s location across the contiguous U.S. — exemplifies how I approach distributive environmental justice research. One of the more consequential methodological decisions we navigated was how to define and measure extreme heat. We ended up using both absolute and relative thresholds because neither alone captures the full picture: some communities face intensely high temperatures in absolute terms, while others face unusual heat relative to their local climate. Together, these two thresholds reveal patterns that either one alone would obscure. Sara’s contributions to the literature review on heat thresholds and the physiological effects of heat on children were genuinely important to how we framed those findings — and a good illustration of how I try to involve students as real intellectual partners in my research, not just as research assistants.

I have made it a point throughout my career to involve students directly in my research as genuine collaborators — this goes back to my former students at previous institutions, including Bruce Mitchell, who helped develop the thermal inequity framework that underlies this line of work, and I am trying now to continue that tradition here at the Bren School. Sara came to this project through ESM 205 (the first EJ core course taught at Bren), already grounded in the conceptual landscape of the field, and her background in psychology gave her a distinct lens for thinking through the negative health impacts of heat on children — one that strengthened this study. What I will say is that what made this collaboration particularly productive was how well-prepared and well-trained Sara is as a Bren student. She arrived with strong analytical skills, genuine fluency in the environmental justice literature, and the kind of intellectual seriousness that let us move quickly into substantive work. That level of preparation is something I have now come to expect from Bren students, and it genuinely makes a difference in what is possible. What I perhaps underestimated going in was the reach this work would ultimately have. Seeing it featured in Scientific American — and seeing Sara experience that moment — reinforced why this model of student involvement matters. It is not only good for the research but it also genuinely changes how students understand what they are capable of.

I think that this study gives policymakers something that did not previously exist: national-scale evidence that shows which student populations are facing the greatest heat burden. The findings are unambiguous — schools serving the highest proportions of Hispanic and Native American students are concentrated in the highest heat exposure categories, regardless of which threshold we use (absolute or relative). Any equitable  policy response must direct resources toward those communities specifically. Infrastructure is urgently needed: cooling systems, shade structures, green spaces, and cool roofs are proven interventions, but they require capital investment that chronically under-resourced school districts typically do not have. Federal climate adaptation funding — through agencies like FEMA and EPA — represents a meaningful opportunity, but only if it is allocated with explicit attention to equity. The findings we have reported here can help make that case directly to funders and legislators.

There are several directions for follow-on research. The current study uses calendar-year temperature data and lacks school-level information on heat mitigation factors like air conditioning or tree canopy coverage — closing those gaps would meaningfully advance our understanding of actual heat exposure. Regional and state-level analyses could also help identify specific districts as intervention priorities, since actionable policy can be developed more effectively at that level. One concrete next step is already underway: I recently co-authored an article with another Bren MESM student (Rebeca Adam) that extends this line of inquiry to the U.S.–Mexico border region, and we have submitted it for publication consideration in another top-tier journal. This region presents a particularly compelling case: it is characterized by some of the most extreme summer temperatures in the country and is home to multiple vulnerable communities with limited capacity to cope with heat exposure. Focusing on this border region allows us to examine thermal inequities at a different geographic scale and in a context where the stakes are especially high.

Reach out to faculty directly and be specific about your interests. Sara’s path into this project began in my first core EJ course at Bren (ESM 205), where she had already built a strong foundation in environmental justice, and that preparation made our collaboration substantive from the start. What made this work as well as it did was not only her initiative, but the quality of training that Bren students bring — the rigor, the interdisciplinary breadth, the grounding in both science and policy. I have always believed in involving students in my research and outreach activities, not peripheral tasks, and it is a tradition I am committed to continuing here. The opportunities are real: research assistant positions, communication roles, and chances to work directly with faculty on projects that reach a broad audience. You have to take that first step yourself — but the faculty here are genuinely eager to include and involve students.