Sleep studies indicate adolescents need between 8.5 and 9.25 hours of sleep each night, according to the National Sleep Foundation. Yet surveys show only 15 percent of young people sleep 8.5 hours or more during the school week, and more than a quarter sleep less than 7 hours.
The foundation says adolescents tend to fall asleep and wake later than younger children because of their physiological changes. The result, they say, is too many teens coming to school too drowsy to learn.
The Center for Applied Research and Educational Improvement at the University of Minnesota also found delaying early-morning start times at the high school level resulted in students being more alert during their first two class periods, with fewer falling asleep at their desks.
Students also were better able to complete their homework during school hours, attendance increased, tardiness decreased and they ate breakfast more often, according to the center's study.
Established in 1990, the National Sleep Foundation is an independent nonprofit group that studies sleep and sleep disorders. In 2000, it released "Adolescent Sleep Needs and Patterns," a report detailing adolescent sleep habits and consequences, and called on educators to address teenagers' sleep needs.