Le Anna King's rose gold iPhone vibrates next to her head at 5:45 every morning on school days, shaking the groggy 16-year-old awake.

The snooze button is tempting, and even when she does force herself off her pillow, she often sits on her bed for a few minutes before getting up to splash water on her face and dig around for an outfit.

Breakfast is out — there's no time. And more often than not she falls back asleep during her bus ride to Central High.

"No teenager I know gets up way early on their own," Le Anna said. "... I'm a good student, but I feel I could be even better if I wasn't falling asleep in some of my classes because I didn't get enough sleep the night before."

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Le Anna, whose classes begin at 7:40 a.m., isn't alone in struggling with early school start times. High schools across the Louisville area have start times that range from 7:20 a.m. to as late as 8:40 a.m.

But an ample and growing body of evidence shows that later class start times have significant benefits, not only for students' rest but also for their academic performance and even social-emotional well-being.

Medical and educational researchers point to findings that adolescents' biological sleep cycles change during puberty, meaning their bodies are wired not to get sleepy until about 11 p.m.

But while tired teenagers may treasure the chance to sleep in a little more, the idea of schools changing their schedules is fraught with passion.

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There are childcare considerations, after-school activities and busing logistics to weigh. And experts say many people don't understand the research behind adolescent sleep, often viewing a later start time as some sort of "mollycoddling" of teens.

The U.S. Centers for Disease Control and Prevention, the American Academy of Pediatrics, the American Medical Association and other major organizations have advocated in recent years for pushing back the start time of the first class of the day; last month, the national Parent Teacher Association passed its own similar resolution on the topic.

But the average start time for middle and high schools in Kentucky, Indiana and across the country continues to be earlier than experts recommend.

JCPS, which is the largest school district in Kentucky, has most of its high school and middle school students starting classes at 7:40 a.m. A JCPS spokeswoman said there are no discussions of making changes to the start times.

Peggy Keller, a professor of developmental psychology at the University of Kentucky, said changing minds — and schedules — is tough.

"American culture doesn't value sleep as much as it should," Keller said. "If we hinder sleep, that can have psychological impacts. But in our culture, it's one thing we're willing to sacrifice in order to get everything done."

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Kyla Wahlstrom, a senior research fellow at the University of Minnesota and one of the leading researchers on school start times, said that "education is the second-slowest institution in the world to change. The slowest is religion."

'A public health crisis'

Wahlstrom said studies show that around the time of puberty, teens have a change in brain sleep patterns, with the release of melatonin — a chemical that makes the brain and body feel sleepy — happening later in the evening.

And given that the average adolescent brain wants to stay asleep about 9 hours and 15 minutes, Wahlstrom said, getting up early could mean teens are going without sufficient rest.

In fact, less than a third of U.S. high school students get at least eight hours of sleep on school nights, according to a 2015 CDC report.

"Any time a school is starting before 8:30 a.m. is counter to the development of the brain," Wahlstrom said.

She has found a number of benefits to pushing back school start times.

She said she's found that high schools that started at 8:30 a.m. or later had higher percentages of students getting the recommended amount of sleep and that correlated to not only better grades and test scores but also to a decrease in at least some cases of tardiness, absences, substance abuse and symptoms of depression.

Studies over the years also have found correlations between later school start times and lower teen car crash rates.

"This is being framed now as a public health crisis for teenagers," Wahlstrom said.

'An emotional issue'

Bullitt County's public high schools start at 7:20 a.m. — one of the earliest start times among districts in the area.

Superintendent Keith Davis said that the current bell schedule started in the early 2000s in response to enrollment growth, with the district needing to do three separate bus runs for elementary, middle and high schools.

Davis said he's led two initiatives to potentially reconsider school start times, saying that the district is aware of the research and recommendations on the subject, but said that community concern has always stopped any efforts to change bell schedules.

In 2009, he said, he asked a committee of parents, teachers and administrators to bring him proposals on modifying start times but "public reaction to the rumors of impending change were such that the board never even formally considered it."

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In 2015, he led a committee to revisit the topic; the committee recommended changing start times, Davis said, but feedback was divided and the board left things alone.

"It is a very emotional issue for many parents and it steps on established patterns and accommodations made over the years," Davis said. "Each time it was discussed, nothing changed and the only real result was a distraction from our core mission, anger and loss of community support."

Tradeoffs for later school hours

At the other end of the scheduling spectrum, Oldham County Schools has most of its middle and high schools start at 8:45 a.m., while its elementary schools start earlier.

Oldham's bell schedules, which have been in place for decades, originally had nothing to do with sleep research, a district spokeswoman said.

But Superintendent Greg Schultz said such a schedule works fairly well for his district since he's seen that younger students tend to be able to get up earlier than older kids. He also pointed to research showing that adolescents often have trouble getting to sleep.

Schultz noted that any schedule requires trade-offs. He said the way Oldham's schedule is set, he sometimes hears worries or complaints about younger students waiting for the school bus in the dark in the mornings and about older students involved in afterschool sports or activities having to start practices later than other districts.

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When Schultz was a high school basketball coach, the gym practice schedule made it so the freshman basketball team was not starting practice until 7 or 8 p.m., he said.

Still, the trade-off appears to be positive, he said, because middle and high school students are getting more sleep.

Wahlstrom said that in the first school district she studied that changed school start times — in Edina, Minnesota — the community's coaches initially pushed back.

But she said that, a year later, she surveyed the coaches again and found most supported the new schedule, with some coaches saying that kids were remembering plays better despite shortened practices.

Schultz said he thinks Oldham's start times help students but added that "start times are not what's making us the district we are." He said much bigger factors are still things like parental engagement and good teachers.

"I wouldn't call Dr. Pollio and say that doing this would transform your district," Schultz said, referring to Marty Pollio, the acting superintendent of Jefferson County Public Schools.

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The JCPS spokeswoman, Allison Martin, was unsure when the district last changed its bell schedules.

Autumn Neagle, the new president of the 15th District PTA, which includes JCPS' school PTAs, said she can understand both sides of the argument of moving school start times.

She knows that no matter what time she puts her 12-year-old son to bed, he likes to sleep until about 9 a.m. And she knows there's research that shows students who start school later tend to be "more awake and conscious of what's going on in the classroom."

But she also understands worries that the later the school day starts, the later extracurriculars and dinner can get. Neagle said her local PTA chapter supports the national organization's resolution.

Could younger kids benefit?

UK's Keller has been doing research that shows that pushing back school start times for younger students could also prove beneficial.

Keller's research found that later school start times in elementary schools was associated not only with better standardized test scores but also in differences in the number of kids getting in trouble for behavior issues.

Keller said a significant portion of brain development happens during sleep and curtailing sleep time means fewer of those key REM cycles during the night.

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Experts say elementary-aged students' sleep schedules tend to be more malleable than adolescents', but it's still important that parents focus on consistent, early bedtimes for younger pupils and of limiting distractions for all students, including electronic devices.

Stacy Simera, communications director for the national advocacy group Start School Later, said many people still have not seen the research on adolescent sleep and school start times.

"Sometimes we think, 'We need to quit coddling those lazy teenagers,' " Simera said. "But no, it's about how our brains are wired."

​​​​​​Reporter Allison Ross can be reached at 502.582.4241. Follow the Courier-Journal's education team at Facebook.com/SchooledCJ.

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