Dive Brief:

• Changes in school start times have a "significant effect" on the amount of sleep and reported grade point averages of students, according to a working paper to be presented at the annual meeting of the American Educational Research Association. The researchers examined eight districts in Minnesota, four of which transitioned to later start times between 2016 and 2019, affecting 38,019 students in grades 5, 8, 9 and 11. 
• Findings suggest districts that moved to later start times saw students' GPAs increase by an average of 0.14 points overall, while predicted GPA increases ranged from 0.10 to 0.17 points. Although the effect on GPAs was "small," said coauthor Rik Lamm, a doctoral student at the University of Minnesota, "it is still meaningful for every student whose grades were helped by only the policy decisions of district leaders."
• In addition, the odds of meeting recommended hours of sleep for students — nine or more hours for students in grades 5 and 8, and eight or more hours for students in grades 9 and 11 — in districts with later start times increased by 16%. 

Dive Insight:

“At a time when school budgets are tight, this is an inexpensive option to increase academic outcomes, as well as the physical and mental health of students, that’s fairly easy to implement,” said Julio Caesar, research scientist in the evaluation and assessment department at Bloomington Public Schools in Minnesota and a coauthor of the paper.

While there have been numerous studies on the physical and mental health improvements associated with delayed school start times, spurring a nationwide movement for the change, studies linking academic outcomes with later start times have been more scarce, the researchers said.

Studies that have investigated the latter point out later start times are linked to better behavior and outcomes for low-income and minority high school students. Later start times have also been shown to benefit middle-schoolers.

Despite pushes for later start times from parents, educators, public health experts and advocates, researchers have found school start times have not changed much over the years. According to 2014 data from the Centers for Disease Control and Prevention, 93% of high schools and 83% of middle schools in the U.S. started before 8:30 a.m.

While the start time recommended by the American Pediatrics Association for middle and high schools is after 8:30 a.m., the majority of schools (76%) in the 2011-12 school year had a start time between 7:30 a.m. and 8:29 a.m. Only 18% of schools started after the recommended time. 

Data from the 2017-18 school year shows, overall, school start times did not change in the following years. Rather, there were a smaller percentage of schools with a start time at or after 8:30 a.m.

However, with the COVID-19 pandemic pushing education leaders to rethink how, where and when learning takes place, now may also be a prime time to consider changes to the school day.  

Utah's Salt Lake City School Board, for example, voted unanimously to delay its high school start times. Others, like West Virginia's Ohio County Board of Education, Massachusetts' Worcester Public Schools, and Minnesota's District 624 have also recently proposed changes as late as 9:15 a.m. 

There are, however, logistical changes and expenses associated with later start times to consider, like altered bus routes. And some districts that have changed to later start times haven't seen the academic improvements boasted by studies. 

Still, researchers wrote in the working paper that the findings should provide school districts with more data to guide potential school start time changes.