Know what you are getting into before tryouts. Each high school program is VERY different in terms of coaching, practices, games etc.... Its a given that HS will have football games in fall on Thurs and/or Friday. Some schools that share stadiums have games on weird nights like Saturday (or Wedns for JV/fish) too though in TX! Some coaches will work with AS kids, some unfortunately will not....had one "sponsor" my freshmen year that would schedule things on the same day and tell the girls to choose! She was awful (luckily I was taking a break from AS that year......)
Look at the high school constitution (and also their practice calendar if online) to see what is mandatory. Typically you are not able to miss summer camp or any games, period. Practices are able to be more flexible, if it is not a consistent occurrence & if you communicate with both coaches prior. Most senior all star teams will be practicing Mon/Wedn odds are, because they know that Thursdays are JV/fish game days and Fridays are Varsity games. Let the allstar coaches know ASAP what the high school practice days are, so they can work around that when choosing what night each team practices. It gets more dicey for basketball season though because it is usually 1 to 2 weeknights a week (could be Mon-Thurs) and there really is no way of knowing which days will be varsity nights vs. JV nights.
I was able to juggle both growing up, as my school team had a "cheerleading" block during the day as an actual class (so minimal after school practice unless it was a special event) . After school, we'd drive straight to the area the gym was located in (1hr with traffic) and have dinner there/do homework. Then we'd drive back after practice and go to sleep, because i had to wake up for school/practice. Repeat, repeat, repeat.
The worst was a year when I had Varsity games on Friday nights that were far away and then a three hour allstar practice at 9am Saturday morning every week in fall. Often times for away games we would get back to the school past midnight (so not in bed before 1am) & then having to wake up at 8am to actually function for a hard practice the next day was horrible. As those have said before, it was also a lot of homework done in the car, to games, and also during/in between class.........I'd finish work for the actual class I was in (especially during electives) and then work on other homework in that class. I remember studying while eating lunch also, though I sat with the national honor society kids so it wasn't a weird thing to see at the table LOL. During basketball season, we were broken up into several small groups (since not all of us could fit on the side of the court at once) and my coach put me in the group that was assigned to game nights that were on opposite days of my allstar practices thankfully.