A pilot study at a small private high school in Providence, R.I., has confirmed the well-documented benefits of a half-hour delay in the school start time for teens, an easy fix for the chronic and rampantly ignored sleepiness of adolescents.
The study shows that two months after the St. George's School changed its start time from 8 to 8:30 a.m., students were getting 45 minutes more sleep on school nights, on average, or nearly eight hours in all. They were going to bed an average 18 minutes earlier, presumably because it felt so good. On Sundays, they spent less time sleeping to catch up.
"Well, for me," one student said, "ever since the 8:30 start I have seen how much good 30 minutes of extra sleep does for me, so I have been inspired to ... get an additional half hour on top of the 30 minutes."
Teens are among the Americans least likely to get enough sleep, according to the National Sleep Foundation, a Washington, D.C.-based nonprofit group and proponent of later start times. Doctors recommend that adolescents get nine hours of sleep on school nights for optimal performance, but the research shows that they average less than seven. According to a recent foundation poll, 80 percent of U.S. teens are not getting nine hours of sleep.
"It's not surprising that a large number of studies have now documented that the average adolescent is chronically sleep-deprived and pathologically sleepy," said Judith Owens, a sleep expert at Rhode Island's Hasbro Children's Hospital and the lead researcher on the St. George's study. The consequences, she said, can range from mood, attention and memory problems to obesity and low grades.
"We're really fighting biology," Owens added. "It's time we started to recognize that sleep is not an optional activity. Adolescents cannot fall asleep much before 11 at night. If they have to start school at 8 a.m., they're not going to get anywhere near the hours of sleep they need."
A number of studies in the past decade have compared high schools and middle schools with different starting times, finding that even a half-hour later start can improve student dropout and attendance rates and help students concentrate. In one study, there was even a drop in the number of crashes due to drowsiness while driving.
The study at St. George's is the first to compare the same students at the same school. More than 200 students, grades nine through 12, filled out online surveys before and two months after the start time shifted to 8:30 a.m. After the change, they reported feeling less depressed and irritated and more motivated to do homework and play sports.
Significantly, fatigue-related visits to the school's health center dropped by two-thirds during the trial period, and the number of students who overslept and were late to first period or missed it completely dropped by nearly half. Students' grades — high to begin with — did not go up, Owens said. (Other studies have seen some correlation between more sleep and better grades.)
The school day at St. George's was not extended. Instead, five to 10 minutes were cut from classes, assemblies and afternoon activities to make up the difference. At the end of the pilot study, the students and faculty voted overwhelmingly to retain the 8:30 a.m. start time.
"Even modest changes can have a big impact," Owens said, adding that her routine improved, too. Her 17-year-old daughter, who attends St. George's, began waking up in a better mood.
"Our mornings are a whole lot nicer," Owens said.
The concept has not caught on beyond a few scattered districts, primarily in Minnesota, Massachusetts and Kentucky. Parents may object to a later start time in high school because they want their teenage children to take care of younger siblings after school. Teachers like getting home earlier, too. And coaches complain that a later start would make it difficult to stay in sync with games at other schools.
The problems are magnified for high schools that start at 7 a.m. or 7:30 a.m.: They would have to shift their start times by an hour or more to reap the benefits, Owens said. Somewhere along the line, for whatever reason, she said, high schools in America began opening earlier in the morning than elementary schools. Now, it's an entrenched practice and a serious public health problem.
No one functions well on inadequate sleep, Owens said: "Adults can't handle it either."
Research shows that teens produce the brain hormone melatonin later at night than children and adults do, prompting a reset of the circadian rhythm, an internal biological clock. They fall asleep up to two hours later than when they were younger.
"On a practical level, this means that the average adolescent has difficulty falling asleep before 11 p.m., so the ideal wake time is around 8 a.m.," Owens said, adding that homework, extracurricular activities and after-school jobs can make it even harder for teens to get the sleep they need.
Although the St. George's study showed marked sleep improvement with a delayed school start time, it fell short of achieving the ideal. Only 11 percent of students reported getting the recommended 9 hours of sleep. Two-thirds said they still felt sleepy doing homework, 18 percent reported falling asleep in a morning class and 36 percent reported napping sometime during the week.
"Probably, 9 o'clock would be the ideal start time for high schools," Owens said.