DENVER, Colo. — Most parents have first-hand experience in trying to get a sleepy child ready for school. While some may think kids need to get to bed earlier, a new study finds it may be better to just start school later. Researchers in Colorado say middle and high school students who start school later experience positive benefits in their sleep health.

Sleep is important for everyone’s overall health, no matter their age. For children, it also bolsters social development and academic achievement. Unfortunately, lack of sleep is a common problem among adolescents.

While an earlier bedtime may sound like a solution, researchers say the real problem is biological. Changes to sleep cycles are common during puberty, which makes falling asleep at an earlier hour tougher for teens. When you combine this with early school start times, it’s a recipe for harmful sleep deprivation.

So when should school start for older kids?

Researchers surveyed around 28,000 elementary, middle, and high school students, and parents in the Cherry Creek School District of Colorado. The team followed this group before and for another two years after the district changed their school start time policies.

Participating elementary schools moved their classes up by 60 minutes. Meanwhile, middle schools started classes 40 to 60 minutes later and high schools started 70 minutes later each morning.

Researchers surveyed children and parents separately, asking each about the student’s bedtime and wake times on weekdays and weekends. Study authors also asked the group to report on the quality of each student’s sleep and incidents of daytime sleepiness.

The results reveal moving school start times back has the greatest impact on high schoolers. Students averaged an extra 3.8 hours of sleep each week after the district changed its policies. The surveys find over one in 10 students also report better sleep quality. One in five said they were less sleepy throughout the day.

Kids feel better on the weekends too

Additionally, high schoolers report having more energy when the weekend rolls around, thanks to later start times. “Weekend oversleep” happens when sleep deprived individuals feel a need to “catch up” on sleep. For high school students, their oversleep fell from two hours on average to just 1.2 hours after starting class later.

Middle school students also experienced a noticeable benefit of starting class later. These youngsters gained an extra 2.4 hours of sleep on average. They also cut down on daytime sleepiness by 12 percent.

For elementary school children, starting class an hour earlier did not lead to higher rates of poor sleep quality or daytime sleepiness.

A proper bedtime is still important

Researchers say they did not find any differences in sleep results when accounting for factors like race and socioeconomic status. They did however see some differences in the times families think is an appropriate bedtime for their kids.

Study authors recommend schools and parents work together to make sure families are getting the proper guidance on how to get children the rest they need. They add that this especially key now, with children across the U.S. going back to in-person learning.

“This study is remarkable due to the large sample size, the inclusion of elementary and middle school students, the two-year follow-up, and both student and parent report. It also provides the strongest evidence to date that moving elementary school start times to 8:00 am caused no significant negative effect on student sleep or daytime sleepiness. As students return to in-person learning, it is important for districts to consider healthy start times for all students,” corresponding author Lisa Meltzer of National Jewish Health writes in a media release.

The study appears in the journal SLEEP.

About Chris Melore

Chris Melore has been a writer, researcher, editor, and producer in the New York-area since 2006. He won a local Emmy award for his work in sports television in 2011.

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