The union's Facilities Action Plan, presented at a packed news conference at its office, is an alternative to the district's consolidation plan, which the mayor-appointed Board of Education approved in April. That plan would move students out of buildings the district describes as aging, underutilized or low-performing.

The closures have drawn sustained opposition from families, staff, students and several City Council members, who have held repeated protests and accused the district of failing to engage affected communities. Councilmembers Jamie Gauthier, Rue Landau and Nina Ahmad attended Wednesday's event but did not speak.

PFT President Arthur Steinberg said the union would deliver its plan to the school board Thursday but voiced little confidence the board would reconsider. He accused the district of years of negligence that let minor maintenance problems escalate into major capital projects, and argued that deteriorating buildings are themselves a driver of the enrollment decline the district cites as justification for closures.

"We cannot allow [the district] to respond to their own failure by closing schools and abdicating their obligation and responsibility to make all district schools safe and healthy," Steinberg said. He called the closures "a pessimistic vision for the School District of Philadelphia's future, and the city as well," and urged Mayor Cherelle Parker to step in, invoking her "One Philly, One Future" budget theme. "I haven't heard one person at the meeting I've attended get up and say, 'Hey, district, this is a great plan,'" he said. "So we're now asking the mayor to intervene. What is more 'One Philly' than the schools?"

The first phase of the union plan would begin immediately and cost roughly $25 million, which the union says is a small fraction of the $548 million the district estimates for deferred maintenance across those buildings. The plan identifies priority work at each of the 17 schools with approximate costs, and projects that if work began now, every building slated for closure would reach at least "good" condition by 2031, with conditions checked daily by people in the buildings.

Jerry Roseman, the union's environmental director, framed the standard simply: "Is my building clean? Is my building safe? Is my building dry? Is my building comfortable? Everyone should answer that yes every day."

The proposal does not cover the more than 150 other district buildings identified as needing modernization, from air conditioning and plumbing to asbestos and lead paint. The union said a second report will follow this calendar year.

In a statement, the district said the union's plan addresses immediate maintenance needs but "does not adequately address the fundamental challenges facing our school system: declining enrollment, aging and underutilized buildings, and longstanding inequities in educational opportunities." The board has said the closures and mergers will proceed.

Faris Carter, who has taught English at Parkway Northwest High School for a decade, said her school is slated for closure even though the district's own measures rate its building in good condition and its surrounding neighborhood as high risk. "How can the district acknowledge a community's vulnerability and then make a decision that threatens its stability?" she said. Carter noted that Parker is a Parkway Northwest alumna and called on her to keep the school open along with the other 16. "Mayor Parker, while campaigning for the office you now hold, you stood on our graduation stage, celebrated our students, and spoke to them about their futures. Now you support a plan to dismantle their school," she said. "You were there when it was time to show off our students. Where are you when it's time to defend them?"

Staff from the affected schools filled the union office and unfurled long scrolls bearing the names of people who, in their words, reject the district's plan and its transition committees.