I witnessed this, then I experienced it.
In the second half of my sophomore year, the bell finally wore out; that is, it just started tweaking one day and completely stopped ringing from that point forward. And so, for the rest of the year, the teachers had to pay attention to the clock themselves, which they sometimes failed to do. Then, on the first day of my junior year, we discovered that they'd finally replaced it.
As for me getting hit with it myself, it had to do with only one teacher having an air conditioner in their class, so the first few weeks of school would always suck, and on some days the last few weeks could be pretty miserable as well — especially if you didn't have a class with that teacher.
Fast forward to the start of the very next year: all of the classrooms with windows in them had an air conditioner installed.
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