(CHICAGO) — Sen. Elizabeth Warren lent her voice to teachers striking in Chicago on Tuesday, addressing a rally of teachers as they called for smaller class sizes and better pay.”I’m here to stand for everyone one of the people who stand for our children every day. Everyone in America should support you in this strike, and the reason is when you go out to fight you don’t fight for yourselves: you fight for the children of this city and the children of this country,” Warren said.”The eyes of this nation are on you… for you to show how the power of standing together is the power of making real change in this country,” the Democratic presidential candidate said.Warren’s appearance in Chicago comes as the strike reaches its sixth day, and the third school day where teachers were not in classrooms.”I believe in public education and I believe it is time in America to make a new investment in public education and I’ve got a plan for that,” Warren said. “America’s public schools need a partner in Washington not a partner who’s going to tell them what to do… not a partner who’s going to pinch pennies, but a partner who’s going to be there to back you up in the critically important work you do every day.”The Chicago Teachers Union is facing off with the city after months of failed negotiations. The union is seeking 15 percent raises over three years plus language in the contract that addresses its school staffing concerns regarding substitute teachers, librarians, school nurses and social workers, according to the Chicago Tribune.Chicago Teachers Union president Jesse Sharkey spoke at the rally shortly before Warren and noted that Mayor Lori Lightfoot had agreed to several of their demands, including ensuring there every school will have a nurse on premises every day. But he rejected the mayor’s request, made in a letter sent to him on Monday that teachers to return to the classrooms while negotiations carry on.”She’s turned in her homework assignment but its only half done,” Sharkey said Tuesday.He noted how the letter said that “there’s no more money, there’s nothing more we can do,” yet also asked for teachers to return to school without the deal being finalized.”I don’t see how those two things go together. How is it that you’re done with us but you want us to go back to work? The mayor might be new but that’s not the way labor negotiations work,” Sharkey said, referencing how the mayor assumed office in May.”We’re not going to work… the city takes us for granted,” he said.Warren released an education plan on Monday and was one of several 2020 candidates to call for higher teacher pay and more money to reduce class size.And while Warren was the only candidate to travel to Chicago since the strike began, she is not the only Democratic presidential candidate to stand with the Chicago teachers.Vermont Sen. Bernie Sanders rallied with the teachers alongside the actor John Cusack during a visit to Chicago last month before the strike was called. Former Vice President Joe Biden, while speaking at an event organized by the United Federation of Teachers in New York City on Sunday, applauded the teachers’ “courage.”Copyright © 2019, ABC Audio. All rights reserved.