Do kids spend 8 hours a day at school now? Back when I was in school, it was 9-3, including an hour for lunch, plus 5 minutes between classes. On top of that, we got a lot more vacation than I've gotten at any job. If I do the math on it, we spent a total of less than 1000 hours a year in school, less than half the time I spend at work in a year.
Plus lunch and 8 minutes between classes.
The school day is from 9 - 4.
This is very different from the school I taught at in Massachusetts which starts before 7am and has seven 45 min classes (plus lunch).
It really all depends on your district. It seems many commenters here believe that all schools work the same way their school works, but they are actually remarkably different across the country.
8h/weeks, 1h homework. Extra activities on 'spare time'. Extra homeworks for those who wishes to compete with elite/private schools on national exams while being substantially given less teachers, less rooms, less credits worse appreciation in a so called meritocratic egalitarian system.
This WAS SPARTA!
This how I was raised. And I wish that to no kids on earth.
EDIT: the idea you got it tough in life will makes you stronger and more likely to succeed is a plain big lie given by the one with a silver spoon in their mouth to divert the attention from their case. The first part is true : you get stronger. The success part is false. Success is mainly a game that is based on rigged randomness.
I used to get on the school bus at 7, start school at 8, go to 2:30 with around an hour for lunch/recess, then two hours of sports practice (or two hours of killing time, then two hours of practice, during basketball season, since we only had one gym), and get home either at 5 or at 7. That's a long day, and throwing an hour or more of homework on top leaves you with pretty much nothing left.
College, now those were the days. 2-3 hours of class, and maybe half the time 2-3 hours of work study.