This Washington Post/SFGate story reports on a study which shows that biologically, 7 a.m. is just too early for high school students:

Carskadon, who teaches human behavior and is director of sleep research at E.P. Bradley Hospital in Rhode Island, led a team of researchers who helped prove that — biologically speaking — teenagers really are out of it early in the morning.

The researchers measured the presence of the sleep-promoting hormone melatonin in teenagers’ saliva at different times of the day. They learned that the melatonin levels rise later at night than they do in children and adults — and remain at a higher level later in the morning.

My high school started at 8:00 AM, though there were some students who took elective classes which did start at 7:00. To this day I have trouble getting up that early–which makes it especially nice to have a job so close to home.