WTF magical school is this? 28C lowered to 23C? Non of schools I gone to even had a such fancy thermostats - just the basic wax based simple ones on heaters - no fucking AC to even see - and if there was - it was only for teachers room lol. So if there was 18C in winter in classes it would be a good day - cause if you are to cold just dress warmer, at summer you simply melted like everything else cause no AC.
Many Japanese secondary schools collect tuition fees, or used to. I imagine this means there's usually money for something more than just older buildings with interiors and furnishings contracted out to the lowest bidder and maybe even money for heating the building
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. Also, in a country where energy's stupid expensive, having decent thermostats saves more money than buying cheap ones. That said, I didn't much mind "rustic" growing up—the old school buildings I knew almost always had a cozier, less hospital-like atmosphere than the new ones imho—but it was clear that the greater investment in education was....inefficient...and that there was still an almost prussian-like mentality about the importance of suffering to build character.