School or sleep?

All throughout high school,I was unable to sleep before midnight or one, which was a little hard on me, because I had to leave for school before 7 am. I became rather too adept at dressing in my elevator. In college, I became a nocturnal creature, going to bed around 3 or 4 and rising around noon.

Apparently, this is natural (I now get up between 7 and 8 without an alarm); teenagers are simply naturally nocturnal for some strange reason. Matt Zeitlin wonders why we don't use this information to schedule school:

In middle school and the high school I would have gone to, class starts at 8:05, while at the school I attend now, classes start at 8:35, and if you’re lucky, you can a first period free at least once a week. Speaking as a sleep starved teenager, those extra 30 minutes in the morning are incredibly valuable. How any school could ever start before 8:00 is simply astounding and probably proof that teachers or some other force has become too powerful in the district, because starting times that absurdly early are never in the interest of the students.

I've often wondered about this in New York City, where staggering school schedules to start at, say 10 would not only let teenagers sleep, but also smooth the usage of the trains rather than crowding kids on at the same time as rush hour commuters. I initially theorized that they were matching the schedules to parents, but by middle school, this isn't a consideration in New York . . . and I doubt much of one in the suburbs either, where I presume most kids take the schoolbus or drive. So how come school starts so early?