In Language Arts a month ago, we were discussing shale drilling. I was explaining how they do it with the hot air and stuff, but I accidentally said "hot ass" instead of "hot gas". I continued speaking for a few more words before I even realized what happened. :D
Lol
"Okay so the hot ass goes into the balloon and then it flie..... WAIT A MINUTE!"
Once a girl was writing "Associative property" on the board and she stopped at "Ass" and started talking to the teacher not realizing what she did.