The Ministry of Education said the stricter rules are intended to encourage healthier digital habits, Bloomberg reported.
Phones are already banned during lesson time, and the updated rules extend that prohibition to recess, CCAs, and enrichment sessions.
Smartwatches are also banned due to their ability to facilitate communication and provide access to social media, potentially leading to distractions, passive screen time, and reduced interaction with peers, the MOE stated.
Students' devices will be stored in designated areas or school bags during school hours, with schools having the discretion to make exceptions for phone use when necessary.
Although the MOE sets the guidelines, schools are given the autonomy to create their own policies in line with the restrictions, as reported by Channel News Asia.
"Where necessary, schools will also put in place disciplinary measures to help students learn the consequences of their inappropriate actions," the MOE said.
For older students in junior colleges and the Millennia Institute, the MOE expects responsible smartphone and smartwatch use.
Additionally, the MOE will now lock personal learning devices, such as tablets and Chromebooks, at 10:30 p.m. instead of 11 p.m. to promote earlier bedtimes. Secondary school students in the city-state have used these school-issued devices since 2021.
Minister of State for Digital Development and Education, Jasmin Lau, shared in an Instagram post that further details about the guidelines will be provided by secondary schools. She also encouraged parents to support these efforts, saying, "I hope parents will continue partnering with us to guide our children toward a balanced and thoughtful use of technology."