Remember the basics of close quarters combat. The second a fight starts, every second you spend swinging and looking is one wasted. Plan before anything starts, take notice of everything - heavy rocks, loose trash, etcetera - any of it will be a useful tool in a fight. The second that they're staggered, either move or get the forget out of there as fast as you can: your focus is on not getting stabbed to death.
The law on knives that you're exposed to results in what these guys have: makeshift weapons and shanks.
These kids are simple as is, trying to embrace chav culture and "play slav" - just keep levelheaded in any fight you get into further on, and keep the teachers in the loop that this is instigated by them, and you're defending yourself to the best of your ability.
