The Los Angeles Unified School District on Tuesday will consider banning smartphones for its 429,000 students in an attempt to insulate a generation of kids from distractions and social media that undermine learning and hurt mental health.

The proposal was being formulated before U.S. Surgeon General Vivek Murthy on Monday called for a warning label on social media platforms, akin to those on cigarette packages, due to what he considers a mental health emergency.

The board of the second-largest school district in the United States is scheduled to vote on a proposal to within 120 days develop a policy that would prohibit student use of cellphones and social media platforms and be in place by January 2025.

The L.A. schools will consider whether phones should be stored in pouches or lockers during school hours, according to the meeting's agenda, and what exceptions should be made for students with learning or physical disabilities.

Nick Melvoin, a board member and former middle school teacher who proposed the resolution, said cell phones were already a problem when he left the classroom in 2011, and since then the constant texting and liking has grown far worse.

"It's a moment whose time has come. When I talk to teachers and administrators and parents, it's one of the number one concerns," said Melvoin.

If approved, Los Angeles would join a number of smaller school districts to ban access to phones or social media. Florida, with some 2.8 million public school students, last year passed a law requiring school districts to prevent student access to social media. Several other states have introduced similar legislation.

While the research on mental health risks remains incomplete, the surgeon general said the emergency was so apparent as to demand action.

He cited a JAMA study showing adolescents who spend more than three hours a day on social media may be at heightened risk of mental illness, while also referring to a Gallup poll showing the average teen spends 4.8 hours per day on social media.

The L.A. school district cited other evidence that cellphone addiction was linked to soaring rates of anxiety and cyberbullying. (Reporting by Daniel Trotta; editing by Donna Bryson and Stephen Coates)