Students who get more sleep do better in school, according to a University of Michigan study which found that a later start time for school results in higher test scores among teens.
Performances on state standardized math tests rose at the district’s high schools — as did average daily attendance — following the move from 7:35 to 8:35 a.m. starts, said university researcher Kyla Wahlstrom.
However, according to the study, there were no significant changes in state reading test results.
Wahlstrom presented the findings to school board members in December.
There was a point of concern for district leaders in the generally favorable report: 88.5 percent of students surveyed at South Washington County’s three high schools reported having a cellphone in their bedrooms.
Simply activating the light on a phone “has the potential for significant disruption of sleep,” Wahlstrom told board members.
South Washington County Superintendent Keith Jacobus said he believed parents should take note of how cellphones can affect sleep. It was perhaps best, he said, to be away from electronic devices for about an hour before bedtime.
For nearly 20 years, Wahlstrom has studied how school start times affect students. She has pushed for later start times for high schoolers, in particular, because she says the teenage brain develops differently than an adult or prepubescent brain.
For teens, the idea of going to bed early to wake up early doesn’t work, Wahlstrom said, because their bodies don’t experience a natural shift into sleep until 11 p.m. — no matter when the school start time might be.
So the later the start, the better the chance of having a student in class ready to go.
About 59 percent of South Washington County students surveyed said they now average eight or more hours of sleep. The average bedtime on school nights was 11:28 p.m. and the average waking time was 7:22 a.m., the study showed.