Later School Start Time Means Happier Students

Starting high school classes just 30 minutes later leads to marked improvement in students' moods and even their overall health, CNN reports. Teens need 8½ to 9¼ hours of sleep a night, and biological changes associated with adolescence mean they naturally fall asleep later than younger kids. In a small sample—200 high school students—starting school at 8:30 rather than 8am lowered the number of students who described themselves as "unhappy, depressed, annoyed or irritated," says a new study.

Fewer students visited the health center complaining of fatigue-related ailments after the change, and attendance improved, reports Scientific American. "If you really need nine hours, and you're only getting six and a half hours or seven hours, even that extra half-hour can make a big difference," says the study's lead author.
(More sleep stories.)