An overwhelming majority -- 98 percent – voted to suspend the walkout and go back to nation's third largest school district. NBC's Rehema Ellis reports.

Updated at 7:08 p.m. ET: CHICAGO -- Union officials agreed to end the Chicago teachers strike, and classes will resume on Wednesday in the nation's third-largest school district.

The Chicago Teachers Union's House of Delegates -- nearly 800 members -- voted to end the strike during a meeting at Operating Engineers Hall, on the city's south side. After the vote, the delegates came out of the hall singing "Solidarity Forever," the Chicago Tribune reported.

The voice vote -- 98 percent in favor -- comes after delegates had a chance to review a contract proposal solidified over the weekend and means roughly 350,000 Chicago Public Schools students will be back in class after seven days off.

The action, however, does not mean an automatic approval of that contract. Ratification of the contract requires a separate vote from the union's rank and file.

Chicago Teachers Union president Karen Lewis says the city's students will be back in class Wednesday after delegates voted overwhelmingly to suspend a seven-day teachers strike. Watch the entire news conference.

"We feel very positive about moving forward. We feel grateful that we have a united union, and that when a union moves together we have amazing things happen," Chicago Teachers Union president Karen Lewis said shortly after the vote.

"We said that it was time, that we couldn’t solve all the problems of the world with one contract. And it was time to suspend the strike,” she said.

NBCChicago.com's Live Blog coverage of Chicago's historic strike

Union delegate Mike Bochner said “an overwhelming majority” of delegates voted for the strike’s end on a voice vote. “I’m really excited, I’m really relieved,” Bochner, an elementary school teacher, told The Chicago Sun Times.

Ahead of the vote, hundreds of parents had gathered outside the Chicago Board of Education to stand with teachers.

"Whatever decision they make today on the proposed contract, we're behind them," Erica Clark, a Chicago schools parent told reporters. "Parents are asking for the same things teachers are asking for."

Chicago Public Schools teachers walked off the job on Sept. 10 after more than a year of slow, contentious negotiations over salary, health benefits and job security. The teachers' previous contract expired June 30 and both sides weeks later rejected a report assembled by an independent fact-finder.

Mayor Rahm Emanuel called the work stoppage "unnecessary" and one of "choice."

While leadership on both sides continued the back-and-forth of contract negotiations, thousands of teachers and their supporters for days took to the city streets in a massive show of solidarity.

Education Nation: Get involved in our 2012 summit, Sept. 23-25

On Monday, Emanuel and CPS attorneys filed a request for an injunction to force teachers off the picket lines, claiming the outstanding issues, as publicly stated by the CTU -- teacher evaluations and recalls -- weren't legal reasons for a work stoppage.

A provision added to the Illinois Educational Labor Relations Act last year prohibits teachers from strike on issues unrelated to economic matters; those involving pay and benefits.

A Cook County judge declined the mayor's request to hold a same-day hearing on the injunction request. Instead, that hearing would have been held Wednesday. With Tuesday's action by the House of Delegates, that hearing is no longer necessary.

The proposed contract includes the following:

The CTU wants a three year contract, which guarantees a 3 percent increase the first year and a 2 percent increase for both the second and third year. It also includes the option to extend the contract for a fourth year with a 3 percent raise;

CPS will move away from merit pay;

The board will hire more than 600 additional "special" teachers in art, music, physical education, world languages and other classes;

One half of all CPS hires must be displaced members;

CPS will evaluate teachers based on 70 percent "teacher practice" and 30 percent "student growth." Additionally, the first year of implementation will not harm tenured teachers and there is a right to appeal the evaluations.

The strike forced parents to find alternative care for their children. Many said they exhausted available vacation time. Others made use of the nearly 150 "Children First" sites that provided students with alternative programming and meals.

As the strike entered its second week, some frustrated parents became more vocal in their demand that both sides end the stalemate. A small group of parents on Monday marched outside CTU headquarters holding signs that read "If you care about the kids, go back to work" and "350,000 CPS Hostages! Let our children learn" and "Don't say you care, show it!"

NBCChicago.com's BJ Lutz and Lisa Balde contributed to this report, as did NBC's Sevil Omer.

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