Researchers at the University of North Carolina at Chapel Hill reported on Mar. 9 that middle and high school students spend nearly one-third of the school day on their smartphones, with frequent checking associated with weaker attention and impulse control.
The study is significant as it provides objective data about how often adolescents use their phones during school hours and how this behavior may affect their ability to focus and regulate attention. By tracking smartphone use every hour over a two-week period, researchers collected thousands of real-world data points, offering a detailed look at phone habits throughout the school day rather than relying on self-reported information or daily averages.
The findings showed that students who checked their phones more frequently demonstrated poorer cognitive control, which is an important skill for learning and academic achievement. Kaitlyn Burnell, research assistant professor at UNC-Chapel Hill and co-author of the study, said, "What surprised us most was the sheer amount of time teens are on their phones during school. Students were on their phones every hour during school, spending one-third of the school day on their phones, with social media and entertainment accounting for over 70% of their time."
By analyzing moment-to-moment phone use, the researchers identified that frequent checking—rather than just total screen time—was closely linked to fragmented attention and reduced self-control. This suggests that repeated interruptions from phone checking may be especially disruptive to learning.
Telzer said, "As states and school districts across the country adopt new phone policies, our findings provide support for limiting access to smart phones during school hours. Policies that restrict access to highly reinforcing platforms, including social media and entertainment apps, during instructional time may help protect students' attention and academic engagement."
The research offers concrete evidence that could inform future policies in schools as well as digital literacy programs. The full paper is available online in JAMA.
