Too Little, Too Late

By Millicent Lawton

East Providence, R.I.

A Brown University sleep researcher has some advice for people who run high schools: Don't start classes so early in the morning. It may not be that the students who have nodded off at their desks are lazy. And it may not be that their parents have failed to enforce bedtime. Instead, it may be that biologically these sleepyhead students simply can't handle the early hour.

"These kids may be being asked to function at the wrong time for their bodies," says Mary A. Carskadon, a professor of psychiatry and human behavior at...