Meeting the teachers at Collège La Grange aux Belles

Here is part of a conversation that I had with Monsieur Philippe Martin (the head English teacher at Collège La Grange aux Belles). It is translated by yours truly:

Me: So, are the kids really that difficult here?
M. Martin: Yes
Me: (trying to find how bad they are) So what kind of things to they do?
M. Martin: Just wait, you'll see....
End of conversation

Ok so does that mean they are bad as in they yell, spit, punch? Or do they have guns and other weapons? Who knows. I guess I will soon find out!