By Marc Kaufman
High school students are less likely to miss classes or stop coming to school regularly if they can sleep later on school mornings, according to the largest study done into the impact of high school start times.
The study of thousands of Minneapolis high school students also found that they got more sleep, got slightly better grades and experienced less depression after the district switched from a 7:15 a.m. start to an 8:40 a.m. start in 1997.
Many districts have made high school classes start earlier in recent years for financial reasons and to accommodate after-school activities. But those near-dawn starts have become controversial around the country as research suggested that teenagers behave better and appear more ready to learn when classes start later. The new research is the most comprehensive yet to look at the issue.
Kyla Wahlstrom of the University of Minnesota, who researched the changes in Minneapolis and earlier in the suburb of Edina, said that officials from scores of school districts nationwide have contacted her about whether they should have classes begin later. The Minneapolis data could help them make their decisions, she said.
"Attendance and continuous enrollment have improved significantly in Minneapolis schools since the start times were changed," she said. "It certainly makes sense that less sleepy students are more likely to stay in school and will be more ready to learn."
In the 1995-96 school year, for instance, an average of 83 percent of ninth-grade Minneapolis students attended classes daily, Wahlstrom found by analyzing attendance records for the entire school district. By 1999-2000, ninth-grade attendance had increased to an average of 87 percent.
Wahlstrom also pointed to a strong effect noted with students "continuously enrolled" in the Minneapolis school district -- defined as being in the same high school two years in a row.
Before the change, she said, only 50 percent of ninth-graders were continuously enrolled, but that increased to 58 percent after the later starts were implemented. For 10th-graders, she said, the percentage of continuously enrolled students grew from 55 percent to 67 percent.
"Something is keeping students from coming and going so much," said Wahlstrom, who conducted the research for the Minneapolis school district and works at the University of Minnesota Center for Applied Research and Educational Improvement.
A smaller analysis involving 3,000 students also found students tended to behave better in school and experience fewer signs of depression after they were able to sleep later, Wahlstrom said.
Some skeptics of the possible benefits of later start times have said that high school students are likely to just go to sleep later if they know they can sleep later on school mornings.
But Wahlstrom also found that Minneapolis students went to sleep at almost the same time before and after the school start switch -- around 10:45 p.m. That means, she said, that they were sleeping about an hour more a night because they were getting up later.
The switch made by Minneapolis in 1997 is being implemented this year in Arlington County, where high school students will report to class at 8:15 a.m., rather than last year's 7:30 a.m. Officials there proposed the change after being persuaded by sleep research that students' natural body clocks make them go to sleep later and wake up later than younger children.
Some parents in Montgomery and other surrounding counties have also lobbied for the change, but school officials have questioned its value and have said it would be expensive and complicated to change bus schedules. Coaches and others who oversee after-school activities -- as well as retailers who hire students -- have objected to any changes, too.
Officials in many districts have also said they will change high school start times only if research shows it will improve student performance and test scores. The Minneapolis research found a slight improvement in grades, but not a significant change.
"There are so many confounding issues surrounding grades that I doubt research will be able to tell us if the later starts produce higher grades," Wahlstrom said.
Advocates of later high school starts were encouraged by the results from Minneapolis. Richard Gelula, director of the National Sleep Foundation, said that he hopes other school districts will follow the city's lead.
"We have known that inadequate sleep affects mood, concentration, memory, error rates, speed and other measures of cognitive performance," he said. "But until the Minneapolis study, we did not know how changing the high school start time from 7:15 a.m. to 8:40 a.m. would directly affect students.
"These findings are a terrific indicator of how much benefit there may be by aligning school start times with the biological sleep patterns of teens, who get too little sleep with current, early start times."
Minneapolis has about 12,000 high school students, and is one of the most economically and ethnically diverse districts in the nation. The suburb of Edina, which implemented later high school starts before Minneapolis and has reported similarly positive results, is a far more wealthy and homogeneous district.
Washington Post August 29, 2001; Page A01
In about six weeks we will again have to suffer the ritual of one of the worst government decisions with respect to our health.
Daylight savings time.
This is one unmitigated disaster. The solution is NOT to turn the clock ahead but start school later and let kids sleep more as the article above describes.
However, this is only a partial solution. The full solution involves recognizing that ideally we should be in bed shortly after sunset. In winter, we all need about nine hours of sleep. This is the average amount of sleep that we had about 100 years ago in the winter, prior to the widespread adoption of electric lights.
But now we are down to seven hours of sleep and counting down. This is just not compatible with ideal health.
This is one of the main reasons why so many get sick with colds, coughs and flus during the winter.
One of the best books I ever read in this area is Light's Out.