KOCO: An eye-opening study says delaying high school starting times by just 30 minutes can reap big rewards for tired teens.

The research found that kids who started school at 8:30 in the morning instead of 8:00 were more alert in class, had better moods and fewer tardies. They even ate healthier breakfasts.

The study was last year at a posh Rhode Island boarding school, St. George's School. Similar results have been found in some public schools that let teens start school late.

Researchers say the reason may be biological; teens are in their deepest sleep around dawn, and have difficulty falling asleep before 11 p.m.

Patricia Moss is St. George's academic dean. She calls the results stunning and says the school has made the change permanent.

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