The Educational Impacts of School Phone Bans: Evidence from Brazil | NBER
Skip to main content
Search
Search
The Educational Impacts of School Phone Bans: Evidence from Brazil
Guilherme Lichand,
Luca Moreno-Louzada,
Thiago da Costa
& Matthew Gentzkow
Share
Bluesky
Threads
Link
Working Paper 35233
DOI 10.3386/w35233
Issue Date May 2026
Concerns about negative impacts of student phone use have led to calls around the world for tighter restrictions on phones in schools. This paper evaluates the impact of a 2023 policy that banned non-pedagogical uses of phones within schools in Rio de Janeiro, Brazil. To isolate the causal effects of the policy, we contrast middle schools that already had strict rules on phone use prior to the policy ("control schools'') to similar schools that did not have strict rules ("treatment schools''), before and after the ban. While restrictions were imperfectly implemented both before and after the ban, we show that in-school phone use fell substantially in treatment schools relative to control. We then show that test scores, which were trending similarly in the two groups prior to the ban, improved by 0.06 s.d. in treatment schools relative to control.
Acknowledgements and Disclosures
We thank the Municipal Secretariat of Education of Rio de Janeiro, which generously shared all details on policy changes and anonymized student data with the research team that made this study possible. We are grateful to Jason Baron, Brian Jacob, Francisco Ramirez, and participants at the UC Berkeley CEGA Research Retreat and the Stanford Tech Impact and Policy Seminar for helpful comments. We acknowledge excellent research assistance by Karine Roncente and helpful exchanges with Juliana Leitão and Kamila Soares Ferreira. The views expressed herein are those of the authors and do not necessarily reflect the views of the National Bureau of Economic Research.
Matthew Gentzkow
I have done economic consulting for Analysis Group and Compass Lexecon. Clients for this economic consulting work include large technology companies such as Google.
Citation and Citation Data
Copy Citation
Guilherme Lichand, Luca Moreno-Louzada, Thiago da Costa, and Matthew Gentzkow, "The Educational Impacts of School Phone Bans: Evidence from Brazil," NBER Working Paper 35233 (2026), https://doi.org/10.3386/w35233.
Copy to Clipboard
Download Citation
MARC
RIS
BibTeΧ
Download Citation Data
Related
Topics
Health, Education, and Welfare
Education
Programs
Children and Families
Economics of Education
Labor Studies
More from the NBER
In addition to working papers, the NBER disseminates affiliates’ latest findings through a range of free periodicals — the NBER Reporter, the NBER Digest, the Bulletin on Health, and the Bulletin on Entrepreneurship — as well as online conference reports, video lectures, and interviews.
2025, 17th Annual Feldstein Lecture, N. Gregory Mankiw," The Fiscal Future"
Feldstein Lecture
Presenter:
N. Gregory Mankiw
N. Gregory Mankiw, Robert M. Beren Professor of Economics at Harvard University, presented the 2025 Martin Feldstein...
2025, Methods Lecture, Raj Chetty and Kosuke Imai, "Uncovering Causal Mechanisms: Mediation Analysis and Surrogate Indices"
Methods Lectures
Presenters:
Raj Chetty
& Kosuke Imai
SlidesBackground materials on mediationImai, Kosuke, Dustin Tingley, and Teppei Yamamoto. (2013). “Experimental Designs...
2025, International Trade and Macroeconomics, "Panel on The Future of the Global Economy"
Panel Discussion
Presenters:
Oleg Itskhoki,
Paul R. Krugman
& Linda Tesar
Supported by the Alfred P. Sloan Foundation grant #G-2023-19633, the Lynde and Harry Bradley Foundation grant #20251294...
Follow
© 2026 National Bureau of Economic Research. All Rights Reserved.