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The Benefits of Letting Students Sleep In

A later start time of the school day is linked to better grades.
high school student fatigue sleep bed

Students' grades increased significantly after their district implemented a new schedule, in which first period began 55 minutes later than before.

What basics do kids need to succeed in school? Proper nutrition. Supportive parents. And then there's that basic necessity we too often ignore: sufficient sleep.

For high school students, getting the recommended eight to 10 hours per night can be nearly impossible when classes start early in the morning. But such schedules are arbitrary, based on tradition rather than science. And new research suggests that changing school schedules can produce positive results.

A new study reports that the grades of second-year science students in two Seattle high schools increased significantly after the district implemented a new schedule, in which first period began 55 minutes later than before. The probable reason: The 2017 sophomores got considerably more sleep than their 2016 counterparts.

"These results offer quantitative evidence that delaying school time is beneficial for students," writes a research team led by Gideon Dunster and Horacio de la Iglesia of the University of Washington. The team's study, "Sleep more in Seattle," is published in the journal Science Advances.

Sleep researchers have long warned that early school start times lead to sleep deprivation among teenagers, as they tend to conflict with students' natural sleep cycles. As de la Iglesia puts it, "To ask a teen to be up and alert at 7:30 a.m. is like asking an adult to be active and alert at 5:30 a.m."

In response to these concerns, the Seattle school district made a major change in the fall of 2016, moving first period of high school from 7:50 to 8:45 a.m. Taking advantage of this opportunity, the researchers enlisted sophomores at two high schools to conduct an experiment as part of a biology class. For six weeks in the spring of 2016 and the spring of 2017, the students (94 in 2016, 84 in 2017) wore wrist-activity monitors day and night.

The sophomores were "instructed to press a marker button on the watch each time they went to sleep and woke up," the researchers write. In addition, they completed a daily sleep diary and completed surveys measuring daytime drowsiness.

On average, the 2017 sophomores got around 34 minutes more sleep per night than their counterparts a year earlier. This brings them "closer to reaching the recommended sleep amount, and reverses the century-long trend in gradual sleep loss," the researchers report.

Their median grades in the biology course were 4.5 percent higher than those of the previous year's class. While it's not certain their increased sleep was a direct cause, "it is certainly reasonable that students who are better rested and more alert should display better academic performance," Dunster and his colleagues write.

Another intriguing finding: Students in one of the two schools, which was made up overwhelmingly of economically disadvantaged students, had "significantly fewer tardies and absentees in 2017 than 2016." There was no similar trend at the other school, which largely serves students from more affluent homes.

That makes sense, as students from poorer families—especially those raised by single mothers—are less likely to have parents with the time and resources to keep a close eye on their attendance. It suggests that kids who are largely on their own are more likely to make it to school if the start time is more reasonable. That, in turn, can help them avoid falling behind their peers.

The researchers caution that moving first period isn't the sole solution for sleepy teens; they argue parents need to intervene to limit "the increasingly pervasive use of screens late in the evening."

But their study provides solid evidence it helps students succeed. It's tough taking notes when you're nodding off.