CHICAGO – The Chicago Teachers Union and district officials said they will negotiate through the weekend, if necessary, to try to avoid a strike Monday. Teachers are ready to walk off the job for the first time in 25 years over issues that include pay raises, job security and teacher evaluations.

There is a lot riding on this contract for Mayor Rahm Emanuel, who has made school improvement a central theme of his administration, and for the teachers union, which feels its ability to protect teachers and give them a voice in education is under attack. Both sides said Friday they are optimistic that a contract could be settled without a strike, although a union spokeswoman said they remained “far apart” on issues such as job security and pay.

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