A national study released this month by researchers at Stanford, Duke, the University of Pennsylvania and the University of Michigan analyzed more than 40,000 schools across the country using data from Yondr, a company that makes magnetic lock bags for students’ cell phones.
The researchers found that the use of cell phones in schools decreased significantly after the schools adopted these bags. Cell phone “pings” from school grounds have decreased by 30 percent, and teachers have reported that non-academic phone use is significantly less in the classroom.
But the study found “near zero” effects on test scores, attendance and cyberbullying, even three years after schools adopted the bags. The researchers compared Yondr schools to schools with similar demographics and academic performance.
At first glance, those findings appeared to contradict a study of Florida schools released last year, which found small academic gains in the year after cell phone restrictions went into effect in 2023.
The researchers who conducted the study, from the University of Rochester and RAND, compared schools where student cell phone use was high with schools where cell phone use was already very low before the nationwide restrictions began. Their reasoning was that schools that had the most mobile phones before the ban should have the greatest impact from the policy change.
Yondr’s national study, in contrast, largely compared schools that use one strict enforcement approach to schools that tend to have softer cell phone restrictions. Some schools in the comparison group still require students to keep phones in backpacks or out of sight during class.
In other words, the national study compared strong versus weak restrictions while the Florida study compared schools with high versus low cell phone use before the ban.
Even with different methods and research questions, researchers from both US studies emphasized in interviews how similar their results were. A Florida study calculated that the academic gain, which occurred in the second year after the ban, was less than a percentile point, equivalent to moving a student from the 50th percentile, dead in the middle, to the 51st percentile. In practical terms, the difference between small profits and near-zero results may not matter.
Both studies also documented an initial increase in disciplinary incidents before behavior stabilized, and both found signs of non-academic benefits, including improvements in school climate or student well-being.
Broader international research, however, remains genuinely mixed.
The first study on the value of cell phone bans, published in England in 2016, found that cell phone restrictions improved test scores especially among low-achieving students. But the Swedish study in 2020 found no academic or behavioral benefits.
The Swedish researchers speculated that their results may reflect the country’s long history of integrating computers into classrooms. In the 1970s, Sweden was one of the first European adopters of technology, so students relied heavily on laptops and other digital devices during lessons before the ubiquity of mobile phones. A separate Swedish study also found that students were more likely to use phones between assignments than during instruction.
Since then, studies in Spain, Norway, Brazil and India have all found educational benefits from mobile phones, although the benefits differed greatly. Randomized trials in India have produced some of the greatest academic gains in literature. Researchers there randomly assigned college students by subject to keep their phones in wooden cubbies before class while others kept them. Unlike most American universities, there were not many laptops or tablets in these Indian classrooms. Removing the phones, in fact, may remove all digital distractions from the classroom.
One possible explanation for the disappointing US results is that students are still surrounded by digital distractions even when phones are gone. David Figlio, lead author of the Florida study, said students often switch to texting, gaming or social media on laptops and tablets that are always allowed at school.
Another possibility is that the educational harm of modern technology is not primarily due to the disruption of the classroom itself. Cell phones can influence sleep, study habits, sustained attention and learning intensity outside of school hours in ways that restricting the school day to seven hours cannot easily reverse.
“Cellphones can still have a significant impact on student achievement, even if cell phone bans don’t change this by a large amount,” Figlio said. “Students may be self-absorbed in their studies, or staying up late and not getting enough sleep.”
Tom Dee, a Stanford education researcher who led the national study, said the “disturbing” findings in this country should not discourage schools from continuing to experiment with cell phone policies.
“We have to continue to iterate, which is something we do often in education policy,” said Dee. “Let’s not move on to the next fad or the next flavor of the day. This issue is too important for us not to stay in the struggle of trying to find a way to manage our children’s consumption in the right way.”
