Drama schools are very small community, a very incestuous community, so you get to know one another very, very quickly and it just washes over after a while. Every now and then I'll say "dude" or I'll say "bro," and people will laugh.
I didn't start drama school until I was 20, and I don't think I would have gotten nearly as much out of it had I gone when I was 18.
I left drama school to do 'The Book Thief' - it was a real trip going straight from school kind of right into it, but I feel like the momentum of being in school put me in a good mindset as far as going into it as a learning experience.