I told a joke in 6th grade (sorry, it involves drawing and is a little Johnny joke, so can't be typed out and be funny). The punchline was good and inappropriate, of course. My teacher overheard and laughed slightly, then said she was sorry, but she had to send me to the vp's office for it.
Naturally, the vp wanted to know the joke, so I asked for paper and busted it out on him. He outright laughed.
He said he wouldn't feel right punishing me after he laughed at my joke and just made me promise to not tell it at school again.
This was in the beforetimes of internet, but you can probably find a version of it somewhere. Good jokes never die. Without ruining the punchline, I'd try searching "little Johnny school drawing mountain horizon". Hopefully the internet hasn't butchered it.
Someone had to do it, so here it is, copied from that place that we have now left:
One morning to spice things up, teacher decided to have a classroom drawing project. One person would start, then the next student would add to the drawing. She asked the students who wanted to start first, so little Johnny raised his hand. Knowing little Johnny had a disturbed mind, she decided to pick Suzie first.
By this point like Johnny could barely control himself. Teacher thought there was no way Johnny could ever turn this into a dirty picture, so he allowed him up to the chalk board.