"If a kid is in first period when they should still be asleep, how much are they really learning?"

Anne Wheaton is an epidemiologist and the lead author of a new study published by the Centers for Disease Control and Prevention. The study surveyed the start times of 8000 middle and high schools across the country. Last year the American Academy of Pediatrics recommended that middle and high schools start no earlier than 8:30 a.m. The goal is to accommodate the "natural sleep rhythms" of teenagers.

Wheaton says that other research suggests nearly two-thirds of young people are seriously sleep deprived. And that can lead in turn to obesity, depression, smoking, drinking, and lower grades. It can even be a contributing factor to car crashes for young drivers.

The CDC found that five out of six schools started before 8:30 a.m. Too early in the researchers' view.

Of 42 states studied, only North Dakota, Mississippi and Wyoming had schools that started at 8:30 or later. In Louisiana the average school start time was 7:40 a.m.

In Montgomery County, Maryland, the school board has been debating this issue for years. It recently voted to start classes 20 minutes later in middle and high school, and 10 minutes later in elementary school.

"The ultimate decision by the board was a compromise," says spokesman Dana Tofig, noting that parents wanted schools to start even later, and that changing bus schedules for 90,000 students this fall is going to be a huge task.

As for the benefits? "I think a lot of it will have to do with what our students tell us ... Are students happier? More engaged with school? Are we seeing less negative behavior or depression?"

And most important, says Tofig, "are they not falling asleep in first period?"

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