To help students regain academic ground lost during the pandemic, schools have often rearranged their class schedules to eke out more time for instruction in individual subjects. But new research suggests adding extra time to the school calendar—rather than rescheduling classes—is what really adds up for students over time.
On average, K-12 public schools operate just under seven hours a day, for about 179 days a year, a total of about 1,200 hours, according to an analysis of more than 70 studies by Brown and Stanford University researchers.
That’s on par with other industrialized countries; the United States tends to have longer school days, but fewer days in the school year. But the national average for the United States hides massive differences across states and communities.
“There are huge inequities in access to learning time within the United States,” said Matthew Kraft, an associate professor of education and economics at Brown University and a research associate at the National Bureau of Economic Research, at a media discussion on learning time this week.
The study found that students who attend schools in the top 10 percent for the amount of time they’re in session receive on average five weeks more instruction every year than do students attending schools in the bottom 10 percent of the spectrum. The differences add up. Over academic careers spanning 12 to 13 years, students in the longest-running schools get nearly two years’ worth of additional instruction.
Federal data suggest more than 1 in 4 public schools have carved out additional time for subjects like math or reading to boost student learning, but only a little more than 1 in 10 schools have added time to their school years.
More districts are piloting longer traditional school years or have added “intersession” classes during vacation, using federal aid from the Elementary and Secondary School Emergency Relief (ESSER) Fund and the American Rescue Plan, according to Bella DiMarco, a policy analyst for the nonprofit FutureEd.
For example, 46 elementary and middle schools in Dallas added five voluntary intersessions weeks for students who wanted more help during vacation periods, and schools near Houston and Richmond, Va., extended their school years to more than 200 days.
Schools with limited learning time can be found in every state and across geographic areas, but are more common in states, like Colorado, that have lower minimum learning time requirements. (Colorado requires 160 school days per year.)
Schools with less scheduled learning time also are slightly more likely to be located in the suburbs and rural areas. In particular, more rural districts have moved to four-day school weeks in an effort to save costs on building and transportation. Research suggests the four-day school week does not tend to improve student achievement.
Non-instructional activities—lunch, changing classes, and so on—account for up to a quarter of the typical school day, Kraft found. While schools can gain instructional time by being more efficient, studies find that extending the school year often provides more benefit than making the school day longer.
“It’s really important to recognize that time matters, but we need to use it well,” Kraft said. “There are likely diminishing returns. If you have a super-long school day, adding a little bit more time probably doesn’t get you as much [effective learning time] as adding an extra day to the calendar if it’s a short calendar year.”