Placing the smallest bloke in the class in a bin arse-first, so far that it comes up to his knees and armpits, and his hands flap uselessly outside. Then lift the bin, place it on the teacher's desk, and await his arrival. Often, the child would panic, and fall off the desk, leaving him semi-conscious in a pile of rubbish on the floor as the teacher entered the room. This is more incriminating, as it simply looks like the kid went mental in the bin, and lost consciousness through rubbish-related hyperventilation.