These are all muck up day pranks:
- Many years ago somebody changed the 'a' in 'grammar' (part of my secondary school's name) to an 'e' on the sign outside, which I thought was pretty funny.
- I had quite an Oxbridge-orientated headteacher so one year someone sent out a letter in his name to the effect that 'all students will be required to apply to Oxbridge and there will be some penalty (I can't remember what it was) if your application is not competitive.' Amazingly lots of parents believed the letter and needless to say there were lots of complaints. The student who wrote it got suspended, but I thought it was funny all the same.
- My GCSE year went absolutely nuts on muck up day. They completely trashed the school and put honey and that paint that leaves a stain on whatever tocuhes it all down the bannisters and around door handles. To be honest, that day wasn't particularly funny.