I dont know about slang, but my form teacher throughout secondary school was big on plays on words and insults.
The only ones I remember now are that he always referred to a classmate with the surname Ashton as Trashpan, and called people things like 'knucklehead' or 'gimmer' if they had displeased him - accompanied by a flying blackboard eraser, something done by several of our teachers back then (70s).
I know from Facebook that he was actually very popular, but at that age I perdonally didn't appreciate his form of humour one little bit.
Nevertheless, again from Facebook, I know that he was a good teacher and a lot of his former pupils really liked him, and he was certainly the only teacher in that school (apart from my French teacher!!!) to teach me any English grammar whatsoever , even though that wasnt his main subject.