hi! I'm a Choatie right now.
dorm life..that really depends on what dorm you're in. dorms range from old houses to big, new buildings to ones that are built in to buildings like the dining hall or the library. small dorms are really tight-knit and homey, and because of their smaller size, it's easier for them to do things like dorm food runs. bigger dorms are also a lot of fun though, and you might enjoy having a larger variety of people to hang out with. dorms do things like mug nights, where advisers put out yummy food like brownies or even grilled cheese sandwiches (my dorm did that once), and at study hours break, people can go out to local vendors that sell food on campus. some dorms also mix grades.
balancing academics and social life..this also depends on the person- courses, extracurriculars, et cetera. in general, it can be difficult. most teachers will make you work hard for your grades, and extracurriculars can eat up a lot of time, like a varsity sport or orchestra. you won't be finding much time to hang out during the academic week except for maybe Wednesdays, which are half-days...unless you're on a team that has a game. weekends are the best time to hang out and relax. in their spare time, people do things like going out to town or walking to Wal-Mart to buy things (taxis are expensive and honestly not worth it). some people just hang out in their friends' rooms and watch movies, and some people go to school dances. some people have sleepovers.
the arts department is great.
but I don't really know what specific art you want to know about.
if you go to Choate, be prepared to see some bad grades that you might've never gotten before. be prepared to work extra hard, but if you just can't finish something, talk to your teacher since most will be understanding. be prepared to cope with stress. get used to having your internet restricted. be prepared to meet tons of new people from all sorts of places. be prepared for some weird weather- this year, it snowed in October. be prepared to walk a lot. and don't be wary of being close with a teacher/adviser! they're all great people, and as a boarding school, it's natural to have teachers in your life, whether it's extra help sessions or making cookies in their apartment.
that was a little long...but if you've got any more questions, feel free to ask! good luck!