Sitthixay Ditthavong / AP
A large group of public school teachers marches past John Marshall Metropolitan High School Wednesday on Chicago's West Side. Teachers walked off the job Monday for the first time in 25 years over issues that include pay raises, classroom conditions, job security and teacher evaluations.
Updated at 3:31 p.m.. ET: CHICAGO -- Classes for the nation’s third-largest school district were canceled for Friday as the Chicago teachers set out to strike for a fifth day, according to NBCChicago.com.
Negotiators trying to bring an end to the Chicago teachers' strike had said they were confident an agreement would be reached soon, but union leaders cautioned parents it was "highly unlikely" students would return to school Friday.
Chicago Teachers Union president Karen Lewis said she hoped an agreement can be reached by the end of Thursday, the fourth day of the strike.
Lewis told reporters she doubts teachers would be back in classrooms Friday, but said she's hoping for a Monday return. "Oh, I'm praying, praying, praying. I'm on my knees for that, please," Lewis told NBC Chicago. "Yes, I'm hoping for Monday. That would be good for us."
Chicago Public Schools chief education adviser Barbara Byrd-Bennett was even more optimistic, saying she was trying to get students back in class by Friday.
"The conversation was productive," Byrd-Bennett said on Thursday. "There was steady and substantial movement on key issues around teacher evaluation and layoffs and recall.”
Chicago's teachers in the nation's third-largest school district went on strike Monday for the first time in 25 years in dispute of education reforms sought by Mayor Rahm Emanuel.
For the first time in days, Emanuel's chief negotiator, School Board President David Vitale, agreed with Lewis' summary of the talks. Only 24 hours earlier, Vitale had threatened not to come back to the negotiating table until the union put forward a better offer.
"We had a very productive evening," Vitale said. "We all go away hopeful that we can go come together on this."
350,000 kids out of school
With more than 350,000 children out of school, the patience of parents had begun to fray as hopes of a quick resolution to the biggest U.S. labor strike in a year faded.
Earlier in the day, civil rights leader Jesse Jackson, who is based in Chicago, appeared at the site where negotiations were supposed to take place on Wednesday and said that he had met with both sides separately to urge them to settle.
Lewis said the progress on Wednesday was on the two most vexing issues -- using student test scores to evaluate teachers and giving more authority to principals to hire teachers.
"We made significant progress on the teacher evaluation side of the equation," Byrd-Bennett told NBC Chicago. "Clearly we're remaining consistent with not wanting to lower the standards for our children. ... I think there were really good discussions."
But Lewis said Thursday, there's still much work to be done.
"We haven't even talked about the professional development side," she said. "We want to make sure this is done right. Doing something fast is not the way to go. Haste makes waste."
The union is concerned that more than a quarter of its membership could be fired because the teachers work in poor neighborhoods where students perform poorly on standardized tests, which Emanuel wants to use to evaluate teachers.
Lewis also said the union fears Emanuel plans to close scores of schools, putting unionized teachers out of work.
Lewis led the walkout on Monday of more than 29,000 teachers and support staff, saying the union would not agree to school reforms it considers misguided and disrespectful.
The dispute jolted the United States, where a weakened labor movement seldom stages strikes and even less frequently wins them. Organized labor has lost several fights in the last year including Wisconsin stripping public sector unions of most of their bargaining power, Indiana making union dues voluntary and two California cities voting to pare pensions for union workers.
The strike in Barack Obama's home city has also put the U.S. president in a tough spot between his ally and former top White House aide Emanuel and labor unions Obama is counting on to win re-election on November 6.
Obama has said nothing in public about the dispute, allowing administration surrogates to urge the two sides to settle.
Obama's own Education Department has championed some of the reforms Emanuel is seeking, and a win for the ambitious Chicago mayor would add momentum to the national school reform movement.
'Difficult for us to understand'
The city is operating 147 schools with non-union staff to offer meals and "keep children safe and engaged," but only a fraction of parents have been using that option, officials said.
At Disney elementary school, several dozen strikers with homemade signs targeting Emanuel and school policies picketed in cool, sunny weather on Wednesday.
Kent Barnhart, a music teacher for the past 25 years, said neighborhood parents had been supportive, offering water and opening their homes and even joining picket lines to march. But he said teachers were frustrated with the slow talks.
"It's difficult for us to understand why they have not truly discussed over the last 11 months things that have been very important," he said of school officials. "It didn't seem like they took it seriously -- really important things like evaluations, health benefits and pay."
Both sides agree Chicago schools need fixing. Chicago students consistently perform poorly on standardized math and reading tests. About 60 percent of high school students graduate, compared with 75 percent nationwide and more than 90 percent in some affluent Chicago suburban schools.
The fight does not appear to center on wages, with the school district offering an average 16 percent rise over four years and some benefit improvements.
More than 80 percent of Chicago public school students qualify for free lunches at school because they come from low-income households.
NBCChicago.com's Michelle Relerford and Lisa Balde contributed to this report, as did The Associated Press and Reuters.
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