No shit. I hated high school for a lot of reasons, but I'm sure I would have done better if it were in session from noon-7 instead of 7-2. What a bunch of bullshit that is. I spend half my day sleeping in class, and they tell me its my fault. Give me a break. I could learn more in two hours if fully awake than I could in 7 hours of half sleep.
I have to say that I experienced the opposite. Throughout all of my high school years, I woke at 5am but still went to bed at 11pm. This has led me to the point where I feel at my best with a minimum of sleep (sometimes as few as just 3 hours, though usually more like 5). For me, there's a pretty noticeable shift in my bell curve of how much sleep I get compared to how I feel. I seem to see most people feel terrible from 0 - 5 hours of sleep, then great between 6 - 9, then bad (or at least not normal) at 9+. However, I feel bad from 0 - 2, good to great from 3 - 7, then pretty weird from 7+. I don't know if that's normal, or if I'm simply not being thorough with my observations.