Second is the nature of the school itself. The Scholomance is basically a pocket dimension that can be accessed from a number of hidden doors/gates/portals from all over the world. We should also decide if it stretches across time as well (meaning you could have people from all different time periods inside the school, which personally seems a little silly to me). The school more or less just IS, rather than being built. It's also an increadible mishmash of all sorts of architecture.
The basic maintence needs and other menial tasks are fulfilled by the bound souls of failed students. The school itself is powered by a diabolic engine - quite literally a demon bound to some sort of abominal machine. The staff of the school are alumni who've decided they'd rather
stick around than return to the real world. There are a few awesome staff members fleshed out
in the threads.
As previously stated, students do murder each other. Murder is not punished unless you are discovered. Running to your teachers to tattle, however, is punishable. Gotta solve your own problems. However, death isn't the only way to do things. Just because you aren't explicitly discovered doesn't mean people won't find out what you've done - magic's involved, after all. Having the reputation of a serial killer will do wonder for your social life. And if you kill someone with the wrong friends... better watch your back. In any case, more subtle methods will often suffice. Domination, black mail, even just showing someone that you COULD have them all have their uses.
There's more fluff (some loose stuff about demons and stuff) but I'm tired of this part, so moving on to mechanics...