From Smartphones to Smart Students: Learning vs. Distraction Using Smartphones in the Classroom

This study evaluates the impact of classroom smartphone use on student performance through two large-scale randomized controlled trials in China. Students were randomly assigned to one of four experimental conditions: (i) smartphones banned, (ii) smartphones allowed and used at will without guidance, (iii) smartphones allowed with teacher prompts to use them for instruction, and (iv) smartphones banned with teachers prompting the use of paper-based aids. Our findings show that unstructured smartphone use reduced performance compared with banning them, whereas teacher-guided use significantly enhanced learning outcomes. Paper-based aids yielded no measurable performance gain over the ban. We analyzed classroom video recordings to track individual-level time spent in each condition. We found that students spent similar total time learning across conditions, but teacher-directed smartphone use produced disproportionately large marginal learning gains outweighing the losses from distraction. Guided use also helped close gender and performance gaps though it risked widening digital divides by major and region. These results suggest educators should receive support to develop purposeful, app-based smartphone instruction materials; policymakers should avoid blanket bans and instead adopt structured usage policies; and tech developers should design classroom-friendly tools aligned with instructional goals. With thoughtful implementation, smartphones can become engines of equity, positive engagement, and learning within the classroom.