My Prank Ideas
Play some of the worst songs in the Apple shop speakers as loud as you can
Have a royal rumble on BMX's
Get a sign saying mining in progress, blocking a public stairway/escalator and get someone to sit/stand there and pick their nose.
Snort 50cm of random stuff
Go sledding on a satellite dish (or any other weird object)
Chain Of Slaps (One person slaps another person who slaps another and this continues in one long chain)