Researchers, doctors, and child development experts have studied what generative AI does to developing brains. Their conclusion: It shouldn’t be anywhere near a classroom, and action should be taken immediately.

“We just don’t want to waste another 10 years in which our kids’ education is undermined,” Leonie Haimson, cochair of the Parent Coalition for Student Privacy, told Fortune. “It took more than 10 years to ban cell phones from schools. We can’t afford that again.”

Boston-based child advocacy nonprofit Fairplay is leading a coalition of more than 250 experts and organizations in calling for a five-year moratorium on all student-facing generative AI products in pre-K through 12 schools in the U.S. and Canada. The group, made up of mental health experts, parents, educators, and organizations geared toward protecting children online, warned that any product that fails safety testing during that pause should be permanently banned. The report, shared exclusively with Fortune, will be released right when advocates rally in front of New York’s City Hall to push for a two-year ban in the city’s public schools specifically.

Fairplay last month led a similar coalition of experts in penning a letter to YouTube and its parent company, Alphabet, to stop the spread of “AI slop” in YouTube Kids videos. The report was coauthored by members of the Screen Time Action Network’s Screens in Schools work group, including Emily Cherkin, a screen time consultant and professor at the University of Washington’s Evans School of Public Policy, along with other experts.