Just got an e-mail from my friend, and her school rules are:
1. No holding hands/hugging/kissing unless instructed to.
2. If you enter a lesson after the bell goes off, you get a de-merit, even if it was like one second afterwards.
3. Always stand up and curtesy/bow when an important member of staff (eg. Head of Year or Headmaster) enters the room. Also do that when you pass them. If you don't do that, you get a de-merit.
4. You MUST have the correct dress code; shirt, tie, trousers/skirts, grey socks, black shoes. One thing out of place, even the tiniest crease (yes, you heard me right, crease) in your shirt means a de-merit.
5. No access to electronics, eg. mobile phones.
6. No eating/drinking unless it's break or lunch. And it MUST be in the dining hall. If you're caught eating at another time or place, it means a de-merit.
7. No going to the toilet except in break and lunch. Even if you're bursting. And if you wet yourself, you get a de-merit.
8. No hair past the shoulders. Even for girls. If you're caught with long hair you get a de-merit.
9. Most ridiculous one; no talking throughout the whole school day unless it's a question to your teacher or requesting something from the dinner hall. If you're caught talking, you get a de-merit.
Three de-merits count up to one detention. There are loads more than this, but these are the only ones I can think of at the moment...