Smarter without phones? What the research on bans can and can't tell us

On January 15, 2026, a neuroscientist named Jared Cooney Horvath sat before the US Senate Commerce Committee and said something that would travel far beyond the hearing room. "Our kids are less cognitively capable than we were at their age," he told senators. Gen Z, he added, "is the first generation in modern history to underperform us on basically every cognitive measure we have."²

The hearing was called "Plugged Out: Examining the Impact of Technology on America's Youth," and its other witnesses included psychologist Jean Twenge and pediatrician Jenny Radesky.¹ Weeks later, Fortune built a story around Horvath's argument, under a headline about "the first generation less cognitively capable than their parents."³

What the hearing actually said

Horvath's main target was not only the phone in a student's pocket. It was the laptops and tablets that schools had handed out. "The answer appears to be the tools we are using within schools to drive that learning," he said.²

He also added a caution. "Now, as Jean said, of course, this is all correlative," he said. "What we really want is causative."² Correlation means two things rise or fall together. It does not prove that one causes the other.

The drop in scores is real. The OECD's PISA tests of 15-year-olds found that average scores fell by almost 15 points in maths and 10 points in reading between 2018 and 2022, and that falling scores were "already apparent prior to 2018." Students distracted by classmates' devices scored 15 points lower than those who barely were.⁴

The witnesses did not agree on the fix. Twenge called for "no phones during the school day bell to bell for students." Radesky took a different line: "I support an approach that puts pressure upstream on tech companies rather than schools."²

The bans arrived before the proof

Governments have not waited. "Mobile phones have no place in schools. No ifs, no buts," England's Education Secretary Bridget Phillipson said in January 2026, as new guidance asked schools to be phone-free through lessons, breaks and lunch.⁹ The Netherlands took phones out of classrooms in January 2024; in a survey of 317 Dutch high schools, three-quarters reported a positive effect on concentration.⁸ In the US, 42 states now restrict phones in public schools, according to a 2026 study in JAMA Pediatrics.¹⁰

Careful studies tell a more mixed story. Researchers David Figlio and Umut Özek followed a large Florida district with a strict bell-to-bell ban. By the second year, test scores had risen a little, but suspensions jumped in the first year, especially for Black boys.⁶ Figlio called the gains "meaningful but not game-changing" and warned that "the policy action is just happening at a level that far surpasses the available evidence."⁵

In England, a study of 1,227 students at 30 schools found that those at schools with strict phone rules had no better mental wellbeing, sleep or grades than students at schools with looser rules. "Our study suggests that school policies are not the silver bullet for preventing the detrimental impacts of smartphone and social media use," said senior author Miranda Pallan. The same team did find that more time on phones overall was linked to worse outcomes.⁷ At a Senate education hearing, Harvard's Martin West put it plainly: "We lack direct evidence of a causal link between smartphones and learning."⁵

Inside the classroom

In a 2024 Pew survey, 72% of US high school teachers said students being distracted by phones was a major problem in their classroom.¹¹ Alex Stegner, a teacher in Portland, Oregon, locked phones away in his classes before his state required it. "I was committed to kind of going all in with it and I liked it," he told NPR.¹²

Students often see it differently. In a Delaware pilot, 83% of participating teachers wanted the ban to continue, while only 11% of students agreed. Zoë George, a New York City senior, said: "I wish that they would hear us out more."¹²

Parents bring another worry. In a National Parents Union poll, 78% of parents whose children take phones to school said it was so they could use them in emergencies. "The phone creates a sense of connection. I want them to know that I am there," said Jenn Silverstein, a parent in Denver.¹³

Questions to think about

If scores were already slipping before 2018, and Horvath blames school laptops as much as phones, how much can a phone ban alone fix? Should schools wait for strong causal evidence, or act on what teachers see every day? And whose voice should count most: teachers, parents, students, or the companies that design the apps?

For the strongest arguments on each side, see our pro and con guide below.