Mayor Bill de Blasio's new plan to tackle school overcrowding calls for a dramatic expansion in the number of classrooms but his own deputies acknowledge it won't solve the problem. NY1's education reporter, Lindsey Christ has more.

More than 500,000 city children attend a public school that is overcrowded. 

The good news — over the next five years the city's Department of Education plans to pay for new classrooms to teach another 44,000 children.

The bad news — The city estimates it needs space for 83,000 more kids.

"In worse cases, children are learning in hallways, students with special needs are receiving services in stairwells," said Shino Tanikawa, co-chair of the Mayor's Advisory Group on School Space. "Children are not getting the attention they need, children are eating lunch at 9:30 in the morning."

At a City Council hearing Tuesday, the Department fielded questions about Mayor de Blasio's new building proposals for the schools. The $14.9 billion dollar plan would expand the system by constructing or expanding 80 buildings. The Mayor also hopes to spend $670 million on new classrooms for his signature initiative, universal pre-kindergarten. 

But education officials acknowledge the plan finances less than 60% of the space they need.

"We remain focused on remedying these issues and will continue to rely on your feedback and support as we do so," said Deputy Schools Chancellor Elizabeth Rose.

The city has also allocated nearly $500,000,000 to remove 350 classroom trailers from schoolyards. But so far, officials have only drawn up plans to relocate half of those students.

And while there are more seats in the latest plan, funding for gym, auditorium and library upgrades has been cut.

But one longstanding issue is finally set to be resolved.

"No PCBs in schools at the end of the year?! Is that what I'm hearing from the testimony? Is that true?" asked Bronx City Councilman Andy King.

"No PCB lighting fixtures," Rose answered.

"Thank you, Thank you, thank you!" King said.

So after many years — and lawsuits — city schools should soon be free of lighting fixtures containing the PCBs, a cancer-causing  compound banned by Congress from new electrical and building materials since 1979.