Kids have to wake up very early in America to go to school. 8am start time means you typically have to be ready to walk out the door at 7:30, and that's a pretty good scenario. If you have a longer commute to school, you might be getting up before 7am.
It's pretty tragic, imo, and it's one of the biggest reasons I want opening hours to shift later.
It's also staggered by grade level. My elementary school started 8am, middle school started 9am, and highschool - the one with the longest commute for most due to there being less and larger schools - started at 7:40am. On that last one, buses dropped us off around 7am, so I had to be out the door by 6:25am.
Here in Europe lessons start as early 7:15 to 8:00, so that's really a good scenario. On the other hand, some other days of the week start as late as 11:45
It's pretty tragic, imo, and it's one of the biggest reasons I want opening hours to shift later.