It's funny that I'm less tired and have more energy as an adult than I did as a child (isn't it supposed to be the other way around?) It's pretty rare that I show up to work in a tired state, but it was a daily occurrence at school.
Kids and teens need a lot more sleep, perhaps 2+ hours more than adults. I recall many slow mornings being harassed by my mom to get up already, it's time to go. Without a helpful mother, oof, I would have missed a lot more days of school.