The Chicago Board of Education is due to vote on Wednesday on a controversial proposal to close 54 schools in the country's third-largest public school district in what would be the largest mass school closing in the nation.

The district's plans to close 53 elementary schools and a high school this year, mainly in Hispanic and African-American neighborhoods, has been met with protests by parents and union leaders who say the closings will disrupt communities and put children in danger with longer walks through troubled areas.

The Chicago Teachers Union, which has clashed with Mayor Rahm Emanuel over other school issues and held a seven-day strike last fall for better pay and conditions, filed federal lawsuits last week to stop the closings.

The Chicago mayor appoints the schools' chief executive and the school board.

"Despite the testimony of thousands of parents, teachers and people who work and live in the school communities impacted, Rahm Emanuel is dedicated to entering the history books as having destroyed the most public schools in one year than anyone," union President Karen Lewis said in a statement.

The vote comes after retired state and federal judges acting as independent hearing officers recommended earlier this month against 13 of the closures.

"We are not underutilized," said Rebecca Nguyen, a teacher at Williams Elementary on the city's South Side who participated in a protest of the proposed closings this week. "We use every classroom in this building."

She said she fears that when her school is combined with another school, "We will not have space for all the children."

Chicago school officials have defended the proposed closings, saying it was necessary to shutter underused schools to help the district reduce a $1 billion budget deficit. The school system has promised displaced students will be sent to better-performing schools with amenities like air conditioning, libraries and upgraded facilities.

When the district first announced the proposed closings in March, it estimated it would save $560 million in repairs and maintenance work over 10 years plus $430 million in operating costs. The district has since reduced the capital cost saving to $437 million over 10 years, attributing the discrepancy to outdated assessments.

MOUNTING PRESSURE

It remained uncertain how the six-member board will vote. But mounting pressure from parents and black aldermen from areas with schools slated for closure under the plan may result in a compromise gesture, according to Dick Simpson, a former alderman and a political science professor at the University of Illinois at Chicago.

"My sense is they will probably relent and not close a handful of schools," Simpson said. "That will still leave 45-50 unhappy sets of parents and teachers."

The closures would also result in the shutting of 61 buildings, which account for about 10 percent of elementary school facilities, according to the district.

Urban school districts around the country have been grappling with declining enrollment, and 70 large or mid-sized cities have closed schools over the past decade, averaging 11 per district, according to the National Education Association, a labor union for school teachers.

This includes Washington, D.C., which closed 23 schools in 2008 and plans to close 15 more over the next two years.

Fueling union anger over school closings in Chicago is the expansion of publicly funded but mostly non-unionized charter schools. The number of charter schools has risen even as neighborhood public schools are closed.

Chicago has promised a five-year moratorium on school closings, following this year.

Parents and school activists have complained that closing neighborhood schools endanger students because they are exposed to greater gang violence if they cross neighborhood boundaries in a city that recorded 506 murders in 2012, largely due to gang violence.

Many of the schools being closed are in the same neighborhoods that have seen frequent gun violence.

Emanuel's ranking in the black community has fallen sharply since the school closing announcements, with 48 percent disapproving of his performance at the half-way point of his first term, compared to a third disapproving a year ago, according to a Chicago Tribune poll released two weeks ago. Among Latino voters, disapproval climbed to 39 percent from 30 percent last year.