After a marathon session in Chicago's Hilton hotel, rank and file members of the Chicago Teachers Union spilled into the street at midnight central time with no contract agreement -- only the promise of a continued strike.

"No deal," a source close to the negotiations told The Huffington Post seven minutes before midnight.

"We came in very optimistic and we left very disappointed," the source later said.

Chicago Public Schools (CPS) spokesperson Marielle Sainvilus confirmed that no deal was reached. She added that both sides planned to meet again on Friday morning.

CPS board president David Vitale concurred. "We've got number crunching to do overnight," Vitale said, according to radio station WBEZ.

CTU is striking for the first time in 25 years, taking to the streets to protest Mayor Rahm Emanuel's education agenda. The latest news comes after parties on both sides said they were inching closer to a resolution. In fact, a source said, the two parties had mostly cleared up the thorny issue of teacher evaluations, agreeing to a scheme that decreased emphasis on the rankings based on students' standardized test scores.

Twenty-five percent of the rankings will be composed of standardized test scores, and another 10 percent will come from teachers' evaluation of student performance, thus satisfying a state law's requirement of relying on performance measures for 30 percent or more after the first year. The agreement also provided more recourse to teachers ranked in the lowest categories. If a teacher's practice or overall score improved, he or she would not be dropped into the lowest category.

The negotiations have proceeded in fits and starts, with breakthrough moments quickly leading to hopeless, locked down bargaining. The source in the room said the biggest sticking points were about salary, contract length and rights for laid-off teachers.

On the salary front, CTU is calling for a 5.8 percent raise, which is higher than CPS's latest offer of an immediate 2 percent increase. Last year, Emanuel yanked a 4 percent raise that was written into the teachers' contract, citing the district's gaping deficit.

"It wasn't so much the 2 percent as much as members still being upset about losing the 4 percent from last year," the source said.

CTU also wants additional rights for dismissed teachers. Currently, if Chicago teachers are laid off, they make $35,000 a year and get benefits working as a substitute teacher as they try to find a regular job. CPS wanted to change that to a day-to-day substitute position that pays $140 a day with no benefits. CTU president Jesse Sharkey told the bigger negotiating team that he estimates CPS is trying to save $100 million overall.

The board and CTU also reportedly sparred about contract length, the source said. CTU wants a two-year contract, largely the union distrusts the mayor after he pulled last year's raise. A shorter contract would also allow another strike before Emanuel's reelection. CPS, the source said, wants a four-year contract, and was not willing to accept a compromise of three years.

CTU President Karen Lewis told reporters outside the Hyatt that she and CPS President Vitale are considering some "creative" methods of resolving the recall issue.

Robert Bloch, CTU's lead attorney, told Catalyst Chicago magazine earlier in the evening that "negotiations go up and down. There are many areas, facets to be worked out."

One of the negotiators told WBEZ about CPS, "They're not playing fair." Catalyst Chicago also reported a negotiator saying that CPS's board "stopped bargaining and dug in their heels."

On Friday, teachers are planning to canvass their neighborhoods then picket at their schools. At 2 p.m., CTU intends to hold a gathering of delegates. And on Saturday, the union will host a "Wisconsin-style" rally.

An Illinois state law passed one year ago made it harder for the Chicago union to strike by requiring 75 percent of its membership to vote in favor. The union had no trouble clearing that bar; 90 percent of Chicago teachers voted to strike this summer after months of sparring with the city.

And teachers aren't the only ones in favor of the strike. A poll conducted by We Ask America found that 56 percent of 1,344 Chicago voters surveyed said they approved of the decision to strike; 40 percent said they disapproved. The strike is especially popular among the city's minorities: 63 percent of African Americans and 65 percent of Latinos approved. Support was also strong among whites.

The strike has been ongoing since Monday, with the union, which represents nearly 30,000 teachers, demanding major changes to the Emanuel administration's education agenda. The union has said it wants a guarantee that principals will be forced to rehire laid-off teachers before looking for new ones, an issue that has come to be known as recall rights.

The union has also demanded significant changes to the way the Emanuel administration wants to evaluate teachers, asking for less of an emphasis on standardized test scores and an overhaul of the consequences associated with the rankings. (An Illinois state law passed recently requires standardized tests eventually to count for 30 to 50 percent of teachers' overall ratings.)

Lewis has said the strike has broader pedagogical goals as well. As she and many other Chicago teachers have explained, class sizes in some schools are exploding and the system doesn't have enough social workers or, in many cases, desks or textbooks. Many teachers have reported teaching in 90-degree weather, since not all school buildings have working air conditioning.

Stay tuned for further updates.

This story was updated at 3:15 a.m. with more details about the negotiations.

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  • Leslie Sabbs-Kizer, Nkai Melton, Akaira Melton, Khaymya Smith

    Leslie Sabbs-Kizer, right, walks her children Nkai Melton, 8, Akaira Melton, 7, and Khaymya Smith, 3 to Bond Elementary school in Chicago, for the first day of classes Wednesday morning, Sept. 19, 2012, after Chicago teachers voted to suspend their first strike in 25 years. Union delegates voted overwhelmingly Tuesday night to suspend the walkout after discussing a proposed contract settlement with the nation's third largest school district. (AP Photo/M. Spencer Green)

  • Students gather outside Benjamin E. Mays Academy , Wednesday morning, Sept. 19, 2012 in Chicago, after Chicago teachers voted to suspend their first strike in 25 years. Union delegates voted overwhelmingly Tuesday night to suspend the walkout after discussing a proposed contract settlement with the nation's third largest school district. (AP Photo/M. Spencer Green)

  • Two students hug, right, as they gather outside Benjamin E. Mays Academy Wednesday morning, Sept. 19, 2012, after Chicago teachers voted to suspend their first strike in 25 years. Union delegates voted overwhelmingly Tuesday night to suspend the walkout after discussing a proposed contract settlement with the nation's third largest school district. (AP Photo/M. Spencer Green)

  • Students walk through the gates outside Benjamin E. Mays Academy, Wednesday morning, Sept. 19, 2012, after Chicago teachers voted to suspend their first strike in 25 years. Union delegates voted overwhelmingly Tuesday night to suspend the walkout after discussing a proposed contract settlement with the nation's third largest school district. (AP Photo/M. Spencer Green)

  • Students gather outside Benjamin E. Mays Academy Wednesday morning, Sept. 19, 2012, after Chicago teachers voted to suspend their first strike in 25 years. Union delegates voted overwhelmingly Tuesday night to suspend the walkout after discussing a proposed contract settlement with the nation's third largest school district. (AP Photo/M. Spencer Green)

  • Rahm Emanuel, Jean-Claud Brizard, David Vitale

    Chicago Mayor Rahm Emanuel, center, is flanked by Chicago Public Schools CEO Jean-Claud Brizard, left, and school board president David Vitale during a news conference after the teachers union House of Delegates voted to suspend their strike Tuesday, Sept. 18, 2012, in Chicago. The city's teachers agreed to return to the classroom after more than a week on the picket lines, ending a spiteful stalemate with Emanuel that put teacher evaluations and job security at the center of a national debate about the future of public education. (AP Photo/Charles Rex Arbogast)

  • Karen Lewis

    Karen Lewis, president of the Chicago Teachers Union smiles as she talks with reporters after the union's House of Delegates voted to suspend the strike Tuesday, Sept. 18, 2012, in Chicago. (AP Photo/Charles Rex Arbogast)

  • Members of the Chicago Teachers Union's House of Delegates celebrate after the delegates voted to suspend the strike against the school district Tuesday, Sept. 18, 2012, in Chicago. The city's teachers agreed to return to the classroom after more than a week on the picket lines, ending a spiteful stalemate with Mayor Rahm Emanuel that put teacher evaluations and job security at the center of a national debate about the future of public education. (AP Photo/Charles Rex Arbogast)

  • Tennille Evans

    Tennille Evans, a member of the Chicago Teachers Union's House of Delegates, celebrates after the delegates voted to suspend the strike against the school district Tuesday, Sept. 18, 2012, in Chicago. The city's teachers agreed to return to the classroom after more than a week on the picket lines, ending a spiteful stalemate with Mayor Rahm Emanuel that put teacher evaluations and job security at the center of a national debate about the future of public education. (AP Photo/Charles Rex Arbogast)

  • Mary Edmonds

    Mary Edmonds, a member of the Chicago Teachers Union's House of Delegates, celebrates after the delegates voted to suspend the strike against the school district Tuesday, Sept. 18, 2012, in Chicago. The city's teachers agreed to return to the classroom after more than a week on the picket lines, ending a spiteful stalemate with Mayor Rahm Emanuel that put teacher evaluations and job security at the center of a national debate about the future of public education. (AP Photo/Charles Rex Arbogast)

  • Teachers picket outside Morgan Park High School in Chicago, Tuesday, Sept. 18, 2012, as a strike by the Chicago Teachers Union continues into its second week. CTU members in the nation's third-largest city will pore over the details of a contract settlement Tuesday as the clock ticks down to an afternoon meeting in which they are expected to vote on ending a seven-day strike that has kept 350,000 students out of class. (AP Photo/M. Spencer Green)

  • Patty Westcott

    Teacher Patty Westcott pickets outside Clissold Elementary School in Chicago, Tuesday, Sept. 18, 2012, as a strike by the Chicago Teachers Union continues into its second week. CTU members in the nation's third-largest city will pore over the details of a contract settlement Tuesday as the clock ticks down to an afternoon meeting in which they are expected to vote on ending a seven-day strike that has kept 350,000 students out of class. (AP Photo/M. Spencer Green)

  • FILE - In this Sept. 14, 2012, file photo Madison teachers hold a unity rally for striking Chicago teachers at the Wisconsin state Capitol in Madison, Wis. Wisconsin's attorney general planned to ask a judge Tuesday, Sept. 18, 2012, to put on hold his decision issued last week repealing major parts of Gov. Scott Walker's law effectively ending collective bargaining for most state workers. The request comes as school districts and local governments attempt to understand the ramifications of the decision and whether it opens the door to new negotiations previously barred with unions. (AP Photo/Wisconsin State Journal, M.P. King, File)

  • Chicago Teacher's Strike Enters Second Week

    CHICAGO, IL - SEPTEMBER 17: Tyler Whitaker watches from a distance as teachers from the Jose De Diego Community Academy, where he is a third grade student, walk the picket line on September 17, 2012 in Chicago, Illinois. More than 26,000 teachers and support staff walked off of their jobs on September 10 after the Chicago Teachers Union failed to reach an agreement with the city on compensation, benefits and job security. With about 350,000 students, the Chicago school district is the third largest in the United States. (Photo by Scott Olson/Getty Images)

  • Smaller, more subdued groups of teachers picket outside Morgan Park High School in Chicago, Monday, Sept. 17, 2012, as a strike by Chicago Teachers Union members heads into its second week. Mayor Rahm Emanuel said he will seek a court order to force the city's teachers back into the classroom. (AP Photo/M. Spencer Green)

  • Chicago Teacher's Strike Enters Second Week

    CHICAGO, IL - SEPTEMBER 17: Striking Chicago public school teachers attend a press conference by The Chicago Teachers Solidarity Campaign outside the office of Mayor Rahm Emanuel in City Hall on September 17, 2012 in Chicago, Illinois. More than 26,000 teachers and support staff walked off the job on September 10 after the Chicago Teachers Union failed to reach an agreement with the city on compensation, benefits and job security. With about 350,000 students, the Chicago school district is the third largest in the United States. (Photo by Scott Olson/Getty Images)

  • Chicago Teacher's Strike Enters Second Week

    CHICAGO, IL - SEPTEMBER 17: Striking Chicago public school teachers attend a press conference by The Chicago Teachers Solidarity Campaign outside the office of Mayor Rahm Emanuel in City Hall on September 17, 2012 in Chicago, Illinois. More than 26,000 teachers and support staff walked off the job on September 10 after the Chicago Teachers Union failed to reach an agreement with the city on compensation, benefits and job security. With about 350,000 students, the Chicago school district is the third largest in the United States. (Photo by Scott Olson/Getty Images)

  • A handful of teachers picket outside Shoop Elementary School in Chicago, Monday, Sept. 17, 2012, as a strike by Chicago Teachers Union members heads into its second week. Mayor Rahm Emanuel said he will seek a court order to force the city's teachers back into the classroom. (AP Photo/M. Spencer Green)

  • Chicago Teacher's Strike Enters Second Week

    CHICAGO, IL - SEPTEMBER 17: Striking Chicago public school teachers picket outside of George Westinghouse College Prep high school on September 17, 2012 in Chicago, Illinois. More than 26,000 teachers and support staff walked off of their jobs on September 10 after the Chicago Teachers Union failed to reach an agreement with the city on compensation, benefits and job security. With about 350,000 students, the Chicago school district is the third largest in the United States. (Photo by Scott Olson/Getty Images)

  • Karen Lewis, Jesse Sharkey

    Chicago Teachers Union President Karen Lewis, left, listens to CTU Vice President Jesse Sharkey speak at a press conference following a meeting of delegates Sunday, Sept. 16, 2012 in Chicago. The Chicago teachers union decided Sunday to continue its weeklong strike, extending an acrimonious standoff with Mayor Rahm Emanuel over teacher evaluations and job security provisions central to the debate over the future of public education across the United States. (AP Photo/Sitthixay Ditthavong)

  • A young boy holds a placard in support of striking Chicago school teachers as they march after a rally Saturday, Sept. 15, 2012 in west Chicago. (AP Photo/Sitthixay Ditthavong)

  • Striking Chicago school teachers march after a rally Saturday, Sept. 15, 2012 in Chicago. Thousands of striking Chicago public school teachers and their allies packed a city park Saturday in a boisterous show of force as union leaders and the district tried to work out the details of an agreement that could end a week-long walkout.(AP Photo/Sitthixay Ditthavong)

  • A young girl plays a toy horn as striking Chicago teachers rally Saturday, Sept. 15, 2012, in Chicago. Union president Karen Lewis reminded that although there is a "framework" for an end to their strike, they still are on strike. (AP Photo/Sitthixay Ditthavong)

  • Karen Lewis

    Karen Lewis, president of the Chicago Teachers Union addresses the crowd during a rally Saturday, Sept. 15, 2012, in Chicago. Lewis reminded that although there is a "framework" for an end to their strike, they are still on strike. (AP Photo/Charles Rex Arbogast)

  • Karen Lewis

    Karen Lewis, president of the Chicago Teachers Union addresses union menbers during a rally Saturday, Sept. 15, 2012, in Chicago. Lewis reminded that although there is a "framework" for an end to their strike, they still are on strike. (AP Photo/Sitthixay Ditthavong)

  • Karen Lewis

    Karen Lewis, president of the Chicago teachers union , left, and vice president Jesse Sharkey stand before a meeting of the union's House of Delegates Friday, Sept. 14, 2012, in Chicago. (AP Photo/Charles Rex Arbogast)

  • Karen Lewis

    Chicago Teachers Union president Karen Lewis arrives for a meeting of the union's delegates Friday, Sept. 14, 2012, in Chicago. The city's nearly weeklong teachers strike appeared headed toward a resolution Friday after negotiators emerged from marathon talks to say they had achieved a "framework" that could end the walkout in time for students to return to class Monday. (AP Photo/Charles Rex Arbogast)

  • David Vitale

    Chicago Board of Education President David Vitale speaks to reporters following negotiations with the Chicago Teachers Union on Friday, Sept. 14, 2012 in Chicago. After a week of public school teachers striking over issues that include pay raises, classroom conditions, job security and teacher evaluations, Vitale said the district and teachers union have agreed on a

  • Public school teachers rally at Chicago's Congress Plaza to protest against billionaire Hyatt Hotel mogul Penny Pritzker, who is also a member of the Chicago Board of Education on Thursday, Sept. 13, 2012. Protesters said that $5.2 million in Tax Increment Financing (TIF) funds being used to build a new Hyatt hotel in Hyde Park would be better spent on meeting basic student needs. (AP Photo/Sitthixay Ditthavong)

  • A large crowd of public school teachers rally at Chicago's Congress Plaza to protest against billionaire Hyatt Hotel mogul Penny Pritzker, who is also a member of the Chicago Board of Education on Thursday, Sept. 13, 2012. Protesters said that $5.2 million in Tax Increment Financing (TIF) funds being used to build a new Hyatt hotel in Hyde Park would be better spent on meeting basic student needs. (AP Photo/Sitthixay Ditthavong)

  • Striking Chicago public school teachers and their supporters march down Michigan Avenue on September 13, 2012 in Chicago, Illinois. More than 26,000 teachers and support staff walked off the job on September 10 after the Chicago Teachers Union failed to reach an agreement with the city on compensation, benefits and job security. With about 350,000 students, the Chicago school district is the third largest in the United States. (Photo by Scott Olson/Getty Images)

  • Striking Chicago public school teachers and their supporters rally following a march down Michigan Avenue on September 13, 2012 in Chicago, Illinois. More than 26,000 teachers and support staff walked off the job on September 10 after the Chicago Teachers Union failed to reach an agreement with the city on compensation, benefits and job security. With about 350,000 students, the Chicago school district is the third largest in the United States. (Photo by Scott Olson/Getty Images)

  • Striking Chicago public school teachers and their supporters march down Michigan Avenue on September 13, 2012 in Chicago, Illinois. More than 26,000 teachers and support staff walked off the job on September 10 after the Chicago Teachers Union failed to reach an agreement with the city on compensation, benefits and job security. With about 350,000 students, the Chicago school district is the third largest in the United States. (Photo by Scott Olson/Getty Images)

  • Teachers picket outside the Chicago Public Schools headquarters on September 13, 2012 in Chicago, Illinois. More than 26,000 teachers and support staff walked off of their jobs on September 10 after the Chicago Teachers Union failed to reach an agreement with the city on compensation, benefits and job security. With about 350,000 students, the Chicago school district is the third largest in the United States. (Photo by Scott Olson/Getty Images)

  • Striking Chicago public school teachers and their supporters march down Michigan Avenue on September 13, 2012 in Chicago, Illinois. More than 26,000 teachers and support staff walked off the job on September 10 after the Chicago Teachers Union failed to reach an agreement with the city on compensation, benefits and job security. With about 350,000 students, the Chicago school district is the third largest in the United States. (Photo by Scott Olson/Getty Images)

  • Striking Chicago public school teachers and their supporters rally before a march down Michigan Avenue on September 13, 2012 in Chicago, Illinois. More than 26,000 teachers and support staff walked off the job on September 10 after the Chicago Teachers Union failed to reach an agreement with the city on compensation, benefits and job security. With about 350,000 students, the Chicago school district is the third largest in the United States. (Photo by Scott Olson/Getty Images)

  • Thousands of public school teachers and their supporters rally outside the Hyatt Regency Hotel to protest against Penny Pritzker, whom they accuse of benefiting from being a board member of both the Chicago Board of Education and Hyatt Hotels on Thursday, Sept. 13, 2012 in Chicago. (AP Photo/Sitthixay Ditthavong)

  • Children in strollers join thousands of public school teachers rallying outside the Hyatt Regency Hotel, protesting against Penny Pritzker, whom they accuse of benefiting from her position on the boards of both the Chicago Board of Education and Hyatt Hotels on Thursday, Sept. 13, 2012 in Chicago. (AP Photo/Sitthixay Ditthavong)

  • Two-year-old identical twins Colton and Lucas Jordan join thousands of public school teachers and their supporters as they march along Chicago's Michigan Avenue, protesting against Penny Pritzker, whom they accuse of benefiting from her position on the boards of both the Chicago Board of Education and Hyatt Hotels on Thursday, Sept. 13, 2012. (AP Photo/Sitthixay Ditthavong)

  • Thousands of public school teachers and their supporters rally outside the Hyatt Regency Hotel to protest against Penny Pritzker, whom they accuse of benefiting from her position on the boards of both the Chicago Board of Education and Hyatt Hotels on Thursday, Sept. 13, 2012 in Chicago. (AP Photo/Sitthixay Ditthavong)

  • Teachers and their supporters rally in downtown Chicago on day four of the strike Thursday, Sept. 13.

  • Teachers and their supporters rally in downtown Chicago on day four of the strike Thursday, Sept. 13.

  • Teachers and their supporters rally in downtown Chicago on day four of the strike Thursday, Sept. 13.

  • Teachers and their supporters rally in downtown Chicago on day four of the strike Thursday, Sept. 13.

  • A large group of public school teachers marches past John Marshall Metropolitan High School on Wednesday, Sept. 12, 2012 in West Chicago. 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. (AP Photo/Sitthixay Ditthavong)

  • A large group of public school teachers rally at John Marshall Metropolitan High School on Wednesday, Sept. 12, 2012 in West Chicago. 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. (AP Photo/Sitthixay Ditthavong)

  • A family waves at a large group of public school teachers as they march on streets surrounding John Marshall Metropolitan High School on Wednesday, Sept. 12, 2012 in West Chicago. 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. (AP Photo/Sitthixay Ditthavong)

  • Chicago public school student Natalia Segal joins the picket line outside of Marshall High School on September 12, 2012 in Chicago, Illinois. More than 26,000 teachers and support staff walked off of their jobs on Monday after the Chicago Teachers Union failed to reach an agreement with the city on compensation, benefits and job security. With about 350,000 students, the Chicago school district is the third largest in the United States. (Photo by Scott Olson/Getty Images)

  • A large group of public school teachers marches past John Marshall Metropolitan High School on Wednesday, Sept. 12, 2012 in West Chicago. 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. (AP Photo/Sitthixay Ditthavong)

  • A young boy in a cart is pulled along by his mother at the tail of a group of public school teachers marching on streets surrounding John Marshall Metropolitan High School on Wednesday, Sept. 12, 2012 in West Chicago. 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. (AP Photo/Sitthixay Ditthavong)

  • Thousands of public school teachers rally for the second consecutive day outside the Chicago Board of Education district headquarters on Tuesday, Sept. 11, 2012 in Chicago. 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. (AP Photo/Sitthixay Ditthavong)

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