Most do not...closer to 5 hours. In any case, it’s the price of having to learn...at least if they’re actually taught anything.
I can’t sit at my desk for five hours...not even close.
In the home school community we were associated with, no kid sat for five hours.
School was seven hours back in the old days. It’s still seven hours today. If you get detention, it’s eight hours. Of course, back then, we got to go outside for recess once or twice a day. We also had music and art classes that helped get our bodies out of desks. We also knew to behave or the principal would introduce us to the board of education and then it was dad’s belt when he got home.