US teenagers are spending more than an hour of every school day on their smartphones, with social media apps such as Instagram, TikTok, and Snapchat consuming the vast majority of that time.
A new study published in JAMA by researchers at the University of Washington School of Medicine reveals that US adolescents average 1.16 hours of phone use during school hours. The findings, based on objective tracking software rather than self-reports, suggest that classroom bans are failing to cut through the digital noise.
“These apps are designed to be addictive. They deprive students of the opportunity to be fully engaged in class and to hone their social skills with classmates and teachers,” said Dr Dimitri Christakis, the paper’s senior author and a professor of paediatrics.
Real-world tracking
Unlike previous surveys that relied on teens admitting to their own screen time, this study tracked the actual behaviour of 640 adolescents aged 13–18. Software installed on their Android devices monitored usage passively between September 2022 and May 2024.
“This moves the conversation beyond anecdotes and self-reports to real-world behaviour,” said lead author Dr Jason Nagata from the University of California San Francisco. “Teens are not always accurate reporters of their own screen time. Objective smartphone data gives us a clearer picture of actual use.”
The data highlighted clear demographic trends. Older adolescents (aged 16–18) and those from lower-income households recorded higher smartphone usage compared to their peers.
While games and YouTube saw some traffic, the “big three” social platforms — Instagram, TikTok and Snapchat — dominated the digital school day.
Bans ‘poorly enforced’
The findings come despite a wave of legislation attempting to curb phone use in classrooms. At least 32 US states and the District of Columbia currently require school districts to restrict student mobile access. However, the study authors warn that policy is not translating into practice.
“To date they’ve been very poorly enforced, if at all,” Christakis noted. “The effect of those policies remains to be seen… I think the US has to recognise the generational implications of depriving children of opportunities to learn in school.”
