Sleeping in probably sounds like a no-brainer to most teenagers, but their parents aren't so sure that it's worth starting school later to get the extra shut-eye.

Half of parents with teenagers whose schools start before 8:30 am said they would like schools to start after that, according to a survey released Monday by C.S. Mott Children's Hospital in Michigan. The later start time was recommended last August by the American Academy of Pediatrics, with the goal of at least 8 1/2 hours of sleep a night for teens.

The pediatricians say more sleep will improve mood and academic performance, and reduce the risk of traffic accidents and obesity.

But just 40 percent of the parents said they thought the shift would mean kids would get more sleep; 20 percent said they thought it would improve academic performance.

The survey doesn't clarify why parents aren't so keen on later starts for middle school and high school. But 22 percent of the 636 parents surveyed said they thought the later start would not allow enough time for afterschool activities.

About half of the parents who favored later start times said they thought the shift should be made only if it didn't impact the school budget.

Sounds like a ringing endorsement of "Hmm," doesn't it?

But it turns out that just 20 percent of the parents had heard about the pediatricians' new policy. Once the surveyors explained it, 71 percent of parents said they agreed with it.

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