Laundry questions go unanswered? What is wrong with you people? 
Okay- I’m a little bit rusty but here goes…
As long as the basic mandatory elements for formal dress BS attire have been met ( coat, tie, shirt, pants and belt )- all is well. The lightly starched - wrinkle free look is out ( and rarely achievable - although I do admire good intentions and spunk! ) The rumpled- I just slept in my clothes look is absolutely in- along with very, very low expectations ( on your part ). Trust me on this one and save your sanity now.
The only thing that requires ( infrequent at best ) dry cleaning during the year is the blazer and an occasional tie. Two or three blazers ( max ) in the closet usually does the trick . One or two navy and whatever else- like a tweed or something. I think two navy blazers is smart but that’s just me. One always gets trashed… so having a backup when it’s likely to count makes sense.
You can dry clean items during breaks ( if your son does his own laundry and you drive him to school ), or you can have your son drop off a few things at the local dry cleaners in town , if allowed - when needed . Or, you can rely on the fact that the laundry service takes your credit card when you sign up so if you do go with the basic wash and fold option and a nice jacket or silk tie somehow finds it’s way into the bag- they’ll dry clean it for you and bill the card on file. Whether or not they still do that as a courtesy automatically, I do not know ( it’s been awhile! ), so I would definitely ask when the time comes- or take your chances and wing it like we did. My boys took 4-5 pants ( indestructible Bill’s, RL or Old Navy khakis and maybe a pair or two of very old broken in cords ), 6-8 button down shirts, 6-8 ties, a few quarter zip sweaters for colder weather under their blazers and 2-3 belts. You can buy all the socks in the world - but most boys at BS will refuse to wear them. It’s this weird BS thing… even in winter! Don’t ask- just go with it.
Boys are super easy to ship off to formal dress BS so don’t sweat it… Compared to girls they’re actually a breeze. Plus, most boys tend to load up on BS swag for downtime overtime so casual wear outside the classroom ( t- shirts, sweats, hoodies, etc ) is a breeze, too. Good luck!!
FWIW- No… I’m not out of CC retirement but you guys are really slacking.