I probably found the weirdest time of being sent home apart from not having injuries is when our sports hall and french rooms flooded, i was gutted about the sports hall, it was my exam that day (Science Mod) and it had to be prosponed.
I think one of the wierdest ones my mate was saying is when the cafe has faulty gas, and it was considered dangerous even though at his school the cafe is on a diffent campus building
Your parents could sue the school for that, as its guideline by law that if a school has to be shut down for either too cold or too hot, then everyone has to leave, not just the juniors.
I've been sent home last summer at 2PM as the rooms got overly hot in one part of the building which didnt have Air Con