Shouldn't this be in the Bully Discussion / Bullworth Experiences section?
Anyway - adults, police & prefects all seem to be classed as authority figures for some reason - and as such, none of the other NPCs will play pranks on them - including kicking them when there's a "Kick me" sign stuck to them.
It is worth noting that planting one on a bully or Jock inside the school often results in some hilarious results - often winding up with your target being busted by the prefects while a gang of geeks & kids are getting stuck in with their feet.
