At the beginning of the month, at the end of one day when my kiddos and I were cleaning up our class for the day, we were all started by a loud cracking noise.
What had happened was that our chalkboard had FALLEN OFF THE WALL!
No one was injured, but the few students who were stacking their chairs in front of it thought that they had done it somehow.
Thankfully we don't use it. I have things taped to it, and come charts stapled right above it, so it's being leaning against the wall until maintenance comes won't be a huge issue. Plus, there's a bookcase in front of one end which should keep it upright for the time being.