Is the national youth theatre like a summer camp- for acting?

i'm a bit confused... i know it says acting classes and all that, but then it mentions accommodation... sorry this might really stupid but why does it mention that, why can't you just stay in your house..? because the website doesn't really give that much information but i know lots of actors went there and since i dont go to a performing arts school it would be good for future cv's and stuff... Thanks :)