Teens spend a third of school day on smartphones

Frequent phone checking - mostly for social media or entertainment - "undermines" the concentration needed to succeed in class, scientists say.

They believe their findings provide evidence for limiting access to smartphones during school hours.

American researchers discovered that middle and high school students spend nearly one-third of the school day on their smartphones, checking them dozens of times.

The findings of the study showed that frequent checking was linked to weaker attention span and impulse control.

The research team examined how often adolescents use their phones during school hours and whether that behavior is related to their ability to focus and regulate attention.

By objectively tracking smartphone use every hour over a two-week period, the study allowing researchers to see how phone use unfolds throughout the school day rather than relying on self-reports or daily averages.

Lead author Dr. Eva Telzer from the University of North Carolina (UNC) at Chapel Hill said: “Smartphones are no longer something students use occasionally during school - they’re present during every hour of the day.

“Our findings show that frequent phone checking may undermine the very skills students need to succeed in the classroom.”

The study, published in the Journal of the American Medical Association (JAMA), found that students who checked their phones more frequently showed poorer cognitive control - a "key" skill for learning and academic success.

Study co-author Dr. Kaitlyn Burnel, also of UNC-Chapel Hill, 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 capturing phone use moment to moment, the research team was able to identify frequent checking, not just total screen time, as a "critical" behavior linked to attention fragmentation and weaker self-control.

They say the distinction is important as it suggests that interruptions caused by repeated phone checking may be particularly disruptive to learning.

Dr. Telzer said: “Our findings provide support for limiting access to smartphones during school hours."

She added: “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.”

Dr. Telzer said the findings provide "concrete, objective evidence" that can inform future school policies, offering a path toward more targeted approaches to managing smartphones in educational settings while preserving the benefits of technology when used intentionally.