Heat-related school closures: a burning issue
26/6/2026
Translation: Katherine Martin
The weather we’ve been experiencing has rekindled a debate about what constitutes reasonable classroom conditions. In the midst of the discussions, I’ve found myself wondering who actually came up with the idea of closing schools during hot weather. And what went wrong in the wake of that decision?
Once upon a time, «school’s closed» was a magic phrase. These days, it’s a cry of exasperation. Switzerland’s German-speaking cantons scrapped heat-related school closures back in 2003 (page in German). These days, with school kids already half-frazzled before the lunchtime bell rings, calls to resurrect the practice are growing louder. Schools, however, have a duty of care, allowing parents to go to work.
In the future, it’ll be up to schools and teachers to decide how to organise classes on hot days.
Well, why don’t they go ahead and organise them? Closing schools to give pupils a break from the heat is a thing of the past. Or is it? Because a glance at the Google News tab would suggest otherwise ...
- French-speaking Switzerland: Schools introduce «heat breaks», sparking criticism (article in German).
- Schools send students home due to the high temperatures, despite heat-related closures being scrapped (article in German).
- Level 4 heat alert: Schools implement heat-related closures after all (article in German).
- Zurich: Schools announce semi-closures, despite guidelines to the contrary (article in German).
- Why heat-related school closures aren’t an option (article in German).
So are heat-related closures a thing? Yes? No? Maybe? Who gets to stay home when it’s hot and who doesn’t? Who’s responsible for deciding? Looking at these headlines, you’d have been forgiven for thinking that everyone was at a bit of a loss. Even before the Teachers’ Union started demanding a nationwide action plan on extreme heat.
Heat-related school closures started in 1863
Teachers and children subjected to non-air-conditioned classrooms or arbitrary decisions by school administrators are the ones having to sweat out heatwaves. Quite literally, in fact. Maybe schools will start having gelato instead of geometry. After all, running a productive lesson in this sweltering heat is a tall order. You’d think even a cursory flick through this kids’ book about climate change (in German) would be enough to get people thinking about a better solution. It’s not as if climate change is a new issue. If societal factors are standing in the way of traditional school closures making a comeback, we at least need to make sure classrooms are cool.
The idea that heat impedes proper learning dates back to a time when modernity was slowly taking hold. Allow me to take you back to the summer of 1863, to the German region of Saxony. A region of gentle accents and gentle hearts. At least when it came to Karl Wilhelm Clauß, the director of a vocational school in Dresden. Clauß may not have had a hot-weather masterplan, but he had sympathy. So when temperatures soared to unusual levels, he sent his students home – a decision that garnered praise in the local newspaper, the «Dresdner Nachrichten».
We were very pleased to learn that classes at Director Clauß’s vocational school were suspended yesterday afternoon due to temperatures of 25° R.
The «R» next to «25°» isn’t a typo. It stands for Réaumur, a temperature measurement roughly equivalent to 31° Celsius. So the Saxons of yesteryear weren’t just a bunch of softies. It’s also remarkable how calmly and appreciatively the news was received at the time. The article continues:
«If it is foreseeable that, at such a temperature, the intellectual benefit that the students receive is zero, then consideration for the children’s physical wellbeing deserves all the more attention. We can only hope that Director Clauß’s commendable approach will receive the proper attention and be emulated in both public and private schools.»
22.5° C at 10 a.m.? Send ‘em home!
That’s exactly what happens. Heat-related school closures become well established, featuring heavily in discussions about school-based healthcare right across the German-speaking world (link in German). Sometimes, temperatures we’d consider springlike today would trigger school closures. In 1887, primary schools in Vienna implemented a rule stating that from 1 June until the end of the school year, afternoon lessons would be cancelled on days when the outdoor temperature in the shade at 10 a.m. rose to 18° R (22.5° C).
This «if the temperature reaches X degrees by Y o’clock, students will be sent home» plan lasted a good 100 years. In fact, it was common practice at the end of the 19th century. Many of us who were educated in Switzerland also remember getting the day off school on scorching days when we were kids. There was always some rule to refer to. What’s more, there was a time when classroom environments were painstakingly scrutinised.
Nothing learned from 150 years of history
The «Schweizerische Lehrerzeitung» (Swiss Teachers’ Newspaper) contains meticulously compiled statistics (in German) on air exchange in classrooms to ensure students would receive «the necessary amount of air». An 1881 report on the canton of Bern states: «Only 137, or 7.5 per cent, of classrooms have special ventilation systems; 92.5 per cent rely on ventilation through windows and doors.»
The report goes on to criticise the fact that not all classroom windows can be opened: «At the very least, such easily remedied defects should no longer be allowed to exist.»
Fast-forward to 2026, the figures aren’t quite as specific. However, in an interview with SRF (in German), Beat Schwendimann, Head of Educational Practice at the Swiss Teachers’ Association, has criticised the lack of investigation into the impact of heat on schoolchildren’s health and the lack of system action taken to combat heat in schools. Some new school buildings, he adds, are being built without air conditioning systems.
That may help to keep construction costs within budget, but it’ll leave the issue of heat-fried brains unsolved. June 2026 was, on average, about four degrees warmer than June 1881.
Source: Swiss Meteorological Observations
Nobody’s getting an A+ in heat management here
Lively debates over the question of when it becomes reasonable to close schools are nothing new. In the unusually hot August of 1911 (page in German), a teacher wrote to the «Zürcherische Freitagszeitung» newspaper proclaiming:
Why close schools because of the heat? I teach at a school, and my students are alert, eager and cheerful in class – more so than at many schools in winter.
He explains this is partly because of him, and partly because of his nice school building: «You see, it depends on the lessons. Three hours in a shady, airy room, then back out after 40 minutes. There’s nothing to complain about there. Factory workers and farmers? They’re worth talking about. People asking for schools to be closed because of the heat are completely useless in school. Neither myself nor my students are requesting closures.»
He’s not wrong, is he? There’s nothing objectionable about doing a lesson in a shady, airy room. How nice for him that he had one. There’s no need to close schools if the conditions inside are bearable and extreme summers are the exception. But when, more than 100 years later, the Teachers’ Association is calling for a renovation campaign to make school buildings and outdoor areas heat-resistant, then something’s clearly gone awry. With the summer holidays just around the corner, that’s what you’d call a failure.
Michael Restin
Senior Editor
Michael.Restin@digitecgalaxus.chSimple writer and dad of two who likes to be on the move, wading through everyday family life. Juggling several balls, I'll occasionally drop one. It could be a ball, or a remark. Or both.
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