Last year, the American Academy of Pediatricians released a policy statement suggesting that middle and high schools should start no earlier than 8:30 a.m. for teens and tweens to ensure that kids in this age group get adequate sleep. Now, in a new report released today by the Centers for Disease Control and Prevention, researchers have found that fewer than one in five schools follow these guidelines.

Using data collected by the U.S. Department of Education, CDC officials reviewed data from the 2011-2012 Schools and Staffing Survey of nearly 40,000 public middle, high, and combined schools to determine school start times. To be fair, this was about three years before the AAP policy statement but let's face it, parents of tweens and teens have known for decades that this age group doesn't do well with the early morning start required at the vast majority of schools. The difference is that studies now show that poor sleep is not just something that teens should learn to deal with; it's a chronic health issue that can lead to obesity and depression and affect a child's performance in school as well as the likelihood the child will engage in risky behaviors.

Pediatricians recommend that kids in this age group get about 8.5 to 9.5 hours of sleep each night. But countless studies have shown that only about 20 percent of kids get this much sleep. According to the 2013 Youth Risk Behavior Surveillance Report, the proportion of high school students who are falling short on sleep (at least two out of every three kids) hasn't changed since 2007.

So, in addition to urging parents to help their tweens and teens get to bed at a decent hour, the AAP and now the CDC are asking schools to consider a later school start time for this age group to help them get more zzz's. According to the CDC's research, 42 states reported that 75-100 percent of the public schools in their states started before 8:30 a.m. And start times varied widely both within and between the states. On average, Louisiana had the earliest average school start time at 7:40 a.m., while Alaska had the latest of 8:33 a.m.

For most schools, start time is dictated by lots of factors — bus schedules, parental work schedules, and staffing schedules to name just a few. And changing the time that middle and high schoolers get started can influence everything from teen work schedules to athletics to start times for nearby elementary schools. Starting school at a later time could also mean that kids who ride the bus might get home in the dark during the winter. And for younger, elementary-aged kids, that could affect the amount of sleep they get each night.

In short, there are lots of reasons why the majority of schools don't want to mess with the status quo when it comes to start times. But there are also plenty of solid reasons why it's an idea worth exploring.

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CDC: School should start later for teens, tweens
New report finds that the majority of middle and high schools start too early.