CHICAGO — Negotiations between union and school officials in the nation's third-largest school district resumed Thursday with an air of optimism and signals that a teachers' strike could end soon.

Chicago Teachers Union President Karen Lewis said students could be back in class by Monday, a week after teachers walked out. Lewis initially suggested classes could resume as early as Friday, then said approval of a final proposal would require a union delegates' meeting, which could take more time.

"We still have some major stuff we have to look at," she told reporters Thursday on her way into the talks. "Doing something fast is not the way to go. Haste makes waste."