I was a dayboy at a boarding school (I lived a short walk away). The school day was from 8:30am until 9:00pm, and we had school on Saturdays as well. Count yourself lucky, my friend.
Anyway, for the last few years of school, I coped by going home after lessons had ended, skipping all the extra stuff that we were meant to be doing, like sports, supervised study times, assemblies, etc. It was technically truancy, but I think of it as the opposite, as I came into school for all my lessons and then skipped the rest. Nobody called me on it, so either they didn't realise (which I doubt), or they didn't bother me because I was still showing up and doing well in all my classes and getting all my work done.
Once I finished my last finals exam, I walked straight home and didn't even return to pick up my stuff.
_________________
If songs were lines in a conversation, the situation would be fine.