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
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
"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,
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
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.
Post August 29, 2001; Page A01