It was a High School AU. I remember all or most of the Avengers being in school together (incl. Wanda and Pietro, who might have been a couple?) and they don't like Tony. They are all going on a school camping trip together and some of the Avengers and Tony are supposed to share a tent, which the group doesn't like at all. At lunch Tony tries to get to know them and wants to sit with them, but they somehow start to fight and it escalates and someone punches Tony in the face. Instead of fighting back, Tony just gets up and leaves without a word.
That's pretty much all I remember. It might have been Stony, but not sure. Any of this ring a bell?