Oh man this was such an experience! I love how you told this story and

had to laugh at this part

The dead body is a reject skeleton from our biology department, but if the kids ever ask where it came from I answer "It is the last student who asked too many questions about skeletons" or "I'm not allowed to talk about it ever since... the incident." (I always use very dramatic air quotes when saying "the incident".)

Then the facepalm moments and the whole laughing about afterwards,

you sound like such a fun teacher.