CHICAGO (Reuters) - Chicago students return to school on Wednesday after a teachers' strike ended, thrilling parents who had to stay home from work to care for their kids, pay for alternative childcare or leave them with friends and relatives for more than a week.

Representatives of the 29,000 striking Chicago public school teachers and support staff voted on Tuesday to suspend their strike and accept a compromise agreement on a new three-year contract with Mayor Rahm Emanuel.

Some 350,000 kindergarten, elementary and high school students return to classes after missing seven school days in the third-largest U.S. school district after New York and Los Angeles.

It was the first time since 1987 that Chicago teachers had walked off the job and nearly everyone in the city seemed relieved that it was over.

"All our members are glad to back with their kids," said Karen Lewis, the outspoken former high school chemistry teacher who heads the union. Lewis led the teachers out of the classroom over Emanuel's demand for sweeping education reforms that the union believed were misguided.

Only a fraction of the students went to nearly 150 centers around Chicago set up to care for children during the strike. The union had warned that the city-run centers would be a "train wreck" with caregivers lacking proper credentials.

While there were no major problems, most parents opted to keep their children at home. Many kids passed the time by watching television, playing video games, doing crafts and chatting on social media.

"They've been around sleeping all day," said parent Dawn McNamara of her daughter, a sophomore in high school, and her friends. "It seemed like it was going to take forever (to settle the strike)," McNamara said.

Teachers were all smiles as they left the vote to end the strike on Tuesday, with one overheard telling a colleague on her cell phone: "Tell our people we're going back. We're going to see our babies."

Even the tough-talking mayor Emanuel choked up slightly at a press conference after the strike was called off. Emanuel said that he fought so hard for reforms because he had seen the blank stares of some children "whose vitality has been stripped from them, any sense of a promise or a future."

"The only way I know to bridge that look in their eyes and the promise and opportunity that exists in the city of Chicago is in the classrooms of the schools," Emanuel said.

While the strike ended, some of the issues that spawned it remain. Most Chicago public schools are struggling academically, the high school graduation rate lags the national average substantially and the school district is in dire financial straits.

Lewis said that the full membership of the union will vote in the next two weeks to formally ratify the agreement, which gives teachers an average 17.6 percent pay rise over four years and creates a new teacher evaluation system based in part on their students' standardized test results.

The teacher evaluation system was a key demand of Emanuel, along with a longer school day. But the union won partial guarantees of job security and fought off Emanuel's attempt to link pay to merit.

A court hearing is scheduled on Wednesday to consider Emanuel's request to have the strike ruled illegal, which was made before the union voted to end the strike. It was not clear if Emanuel's legal case against the union would continue.

The union also filed an unfair labor practice charge against the school district during the dispute and litigation may continue on that grievance before a state agency.

Teachers said they fear now that the strike has ended, Emanuel will proceed to close dozens of schools to help pay for the cost of the agreement with teachers.

The Chicago Tribune reported last week that the school district is considering closing 120 schools and a local education information service, Catalyst Chicago, said its analysis suggested as many as 140 schools met the district's criteria for closing.

Like many large cities, enrollment in Chicago public schools has fallen in recent years as population declined, and some people move to the suburbs. The district says it needs to close schools to reduce overcapacity. The union says that the district is closing neighborhood public schools and replacing them with "charter" schools, which are mostly non-union.