I can't recall if poor behaviour in inner city schools was always so overtly sexualised, or if it's a recent adaptation.
Standing watching fifteen year old Joe happily and frenziedly miming sexual congress with a wooden chair one foot away from me, I apply the fixedly evil eye, grimly judge which comments will shame him into ceasing that particular hobby, and try hard to contain or disguise my utter disbelief.

Actually, thinking back to my first week of teaching, when a class of thirteen year olds blew a condom up until it became a fifteen inch diameter balloon, then batted it playfully around the class in front of me, perhaps it's not changed.
More likely, as I've grown older, adolescents begin to seem younger, and their inevitable obsession with sex more outre.

[weary irony] So that's alright, then.