Clearly you and I participated in very different school experiences. In highschool, I got on my bus each day at 7:30 and got back off the bus at 16:00. If you subtract the 30 minute lunch period, that adds up to almost exactly 8 hours each day.
Factoring in the 2 hours of homework that was regularly assigned, I actually have substantially more free-time as a working 9-5 adult (my school did not have “study hall” time). A young me would have done unspeakable things for a chance at abolishing homework!