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Jackson Hole High School might have some of the best-rested teenagers in America. The Wyoming high school used to start class at 7:35 a.m. — earlier than the average American high school, but not by much.
In 2012, though, the school district listened to a growing chorus from researchers, pediatricians, economists and others who say high schools should start later than they do. They moved their start time back more than an hour, to 8:55 a.m.
After the change, students reported sleeping more. They were more likely to show up to class on time. It's even possible that the later start date contributed to a dramatic drop in car crashes in the district.
But Jackson Hole's 8:30 start is an outlier. Most high schools start the day way earlier — a survey of 18,000 public high schools in 2011 found that the average start time was 7:59 a.m. The vast majority, 86 percent, started before 8:30 a.m.
And the evidence suggests that's bad for kids' health and their grades. Teens might be able to do better, pediatricians argue, if we just let them sleep a little bit later.
Adolescents are wired to sleep later
Medical research has found, contrary to public opinion, that teenagers aren't lazy —they just have a different relationship to sleep.
Adolescents should get 8.5 to 9.5 hours each night like other kids, according to the American Academy of Pediatrics, which recently recommended later high school start times. But here is what's different about teenagers' sleep cycle changes: they shift about two hours later than when they were younger.
That means that while a child in elementary school might be happy to fall asleep by 9 p.m. and wake up before 7 a.m., an adolescent is better off falling asleep at 11 p.m. and waking up at 8 a.m. That's after class is underway in the vast majority of high schools across the US.
The gap between how much sleep people need and how much they get is wider for adolescents than for any other age group. A poll from the National Sleep Foundation found that more than half of parents estimate that their 15- to 17-year-olds sleep less than 7 hours per night.
Other studies have found less dire results. The Bureau of Labor Statistics' American Time Use Survey found that high school students sleep about 8.5 hours per night on weekdays.
There are health risks associated with lost sleep — everything from falling asleep while driving to higher risks for obesity and depression. And given adolescent sleep schedules, pediatricians' group suggested that the ideal start time for high school is 9 a.m. Other researchers say even later would be better.
High schools start earlier than teenagers want to wake up
While none of the research on high school start times meets the gold standard of a randomized controlled trial, some studies suggest that students are paying an academic price for waking up too early.
A study of first-year students at the Air Force Academy found that students who weren't assigned to 8 a.m. classes had higher grades across the board than students who took earlier classes. Research in Chicago Public Schools found that the later in the day students studied English and math, the higher they scored on standardized tests at the end of the year. After controlling for various characteristics, test scores went up in North Carolina's Wake County School District when middle school started an hour later.
A study of later start times in Minneapolis Public Schools found no effect on ACT scores, although researchers point out that students generally take the test early in the morning, which could throw off any benefits from starting school later on normal days.
Starting school later, though, might also have other benefits. A research center at the University of Minnesota studied eight public high schools in three states that shifted to later start times.
The university researchers found that when schools started at 8:30 a.m. or later, more kids got at least eight hours per sleep. At some schools, students were less likely to be tardy when school started later. And at two schools in the study, car crashes fell dramatically: 65 percent, from 17 crashes to six, at a school district in Minnesota, and 70 percent in the Teton County School District, whose high school is Jackson Hole High School.
The Hamilton Project at the Brookings Institution, a Washington, DC, think tank, estimated that starting high school later could lead to students making $17,500 more over the course of their lives because they'd learn more.
Still, reform isn't likely any time soon
Most policies that are supposed to raise test scores — everything from better-paid teachers to the Common Core — turn out to be highly controversial. Starting school later isn't.
But that doesn't mean it's without a downside. In this situation, the problem is usually logistics. Students of all ages usually share the same fleet of buses. High school students get the first shift, and the buses circle back to pick up their younger siblings later in the morning.
Most districts don't want elementary school students to have to wait in the dark for buses early in the morning — nor do they want to pay for a separate fleet of school buses for elementary and middle school kids. Breaking with tradition turns out to be costly.
In Virginia's Fairfax County, for example, the first buses start to pick up high school students at 5:45 a.m.; middle and high schools in the district start class at 7:20 a.m. The school board is considering four proposals to help high school students get more sleep; all would start the school day after 8:10 a.m.
The four proposals have a projected cost of between $2.8 million and $7.6 million. That's only a small fraction of Fairfax's $2.5 billion budget for 2015, but it's a large price tag for a policy change.
In these scenarios, logistical concerns often end up ruling the day. The district's school board will decide on a plan to shift its start time later this year.
