Striking Chicago teachers rally to wrap labor deal Scott Olson / Getty Images Chicago Teachers Union President Karen Lewis speaks to supporters Saturday during a rally at Union Park in Chicago, Ill. CHICAGO -- Thousands of striking Chicago teachers rallied on Saturday to keep the pressure on Mayor Rahm Emanuel to wrap up an agreement with their union to end a strike that has closed the nation's third-largest school district for a week. The rally brought labor leaders, community activists and teachers to Chicago's Union Park for one of the largest demonstrations against Emanuel's education reforms since the strike began Monday. "You have proven to the world that you're not going to take it anymore," Lorretta Johnson, secretary-treasurer of the American Federation of Teachers, told demonstrators the day after the two sides reached a tentative labor deal. See strike coverage and more Chicago news at NBCChicago.com Kids may be back in school Monday if the Chicago Teachers Union is able to reach an agreement about salary increases, teacher evaluations and rehiring policy for laid-off teachers. "We are on strike," CTU President Karen Lewis told the crowd estimated to be about 25,000 decked out in red. We have a framework; we do not have an agreement. Lewis was one of 20 speakers who spoke at the event, which lasted more than two hours. Led by Lewis, a former high school chemistry teacher, 29,000 unionized teachers, counselors, nurses and other support staff staged their first strike in 25 years, leaving 350,000 Chicago students with no school this week. Emanuel angered the Chicago teachers by trying to push through proposals to radically reform teacher performance evaluations and weaken job protection for teachers whose schools are closed or perform poorly academically. Emanuel retreated from some of his proposed reforms, although details of what he has agreed to with the union have not been made public. Negotiators for the mayor and the union announced a tentative agreement on Friday that could lead to an end to the strike. The confrontation has left many Democratic mayors and politicians supporting Emanuel, a former White House chief of staff for President Barack Obama. Other Democrats have sided with the unions, which are major financial supporters of the party and are needed to help Obama win re-election in November. Emanuel denied Saturday there had been any pressure from the White House to settle the strike. "The short answer is no," Emanuel's spokeswoman, Sarah Hamilton, said. There was no pressure, and no pressure would have worked, because they know that the mayor firmly believes that what we are doing to reform and improve our schools is the right thing. The union is wary of Emanuel, who has been called a "bully" and a "liar" by Lewis. Organizers hoped Saturday's rally would rival some of the huge demonstrations last year that protested the efforts of Republican Wisconsin Gov. Scott Walker to curb the power of unions. The Wisconsin protests were unsuccessful but drew tens of thousands of government workers, including teachers. Activists and supporters from other unions joined the sea of strikers wearing red T-shirts at Saturday's rally. "This is not just a Chicago struggle; this is a struggle for workers everywhere," civil rights leader Jesse Jackson said. You've led a new struggle for courage. If all goes well in the negotiations between the Chicago School Board and the union this weekend, Lewis said she would ask some 800 union activists on Sunday to suspend the strike and teachers would return to classrooms Monday morning.