Sleepy in the day and wide awake at night? Give the screen a rest. Guido Mieth/Getty Images/Flickr RM hide caption

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About 40 percent of high schools start before 8 a.m., which contributes to chronic sleep deprivation among teens, according to the American Academy of Pediatrics. Chris Waits/Flickr hide caption

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Teenagers' sleep patterns may be a clue to their risk of depression. iStockphoto hide caption

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Daniel Horowitz for NPR

Solid friendships can help buffer life's stress. iStockphoto hide caption

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Maggie Starbard / NPR

It may not be the best strategy to stay up late and cram. A new study finds that when teens don't get the sleep they need, all kinds of things can go poorly. iStockphoto.com hide caption

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