UPDATED: 8/29/2012 10:55 a.m.

CHICAGO (CBS)– The Chicago Teachers Union apparently is ready to strike.

A source tells WBBM Newsradio’s Bernie Tafoya that CTU President Karen Lewis plans to file a 10-day strike notice on Wednesday. That means teachers could walk off the job as soon as the end of next week, which is also the end of the first week of school for most public schools.

At Brunson Elementary on the West Side, school chief Jean-Claude Brizard conducted a round-table discussion on Wednesday with principals who are on year-round schedules to hear how they’ve implemented the longer school day.

Afterwards, Brizard said a strike is the last thing Chicago’s students need, but the district has to be prepared.

“Right now, we’re planning what we can and cannot do.” he said. “We cannot provide classroom teaching for our kids. That’s unfortunate. They’ll be losing a lot, so that’s the one thing we cannot provide for. We’re looking for what else we have to provide as a community to make sure our kids are safe and fed.”

CBS 2’s Dana Kozlov has learned Chicago Public Schools officials are ready for the worst.

LISTEN: WBBM Newsradio’s Bernie Tafoya Reports

CPS officials have been waiting to be notified about a strike – hoping to avoid it altogether.

The plan to file a 10-day strike notice follows what sources said have been “marathon negotiating sessions” over the past couple weeks.

At a town hall event Tuesday evening, Lewis indicated both sides are still far apart on many issues.

“I think the problem is, people have been so focused on pretty narrow issues, not understanding that this is a really bigger battle, and a bigger fight,” Lewis said.

The strike notice would not necessarily mean teachers would go on strike in 10 days if a contract deal is not reached in that time, but it would put more pressure on both sides to reach an agreement.

CPS officials said they had not heard anything directly from the union about a plan to file an official strike notice as of Tuesday night. Lewis was set to meet with other union delegates, but last week, the CTU House of Delegates gave her the authority to give a 10-day strike notice at her discretion.

The Chicago Board of Education has budgeted up to $25 million to provide alternative programs for students in the event of a strike. The focus would be on providing a safe environment, with positive activities, and on feeding the 80 percent of CPS students who are low-income and depend on school meals.

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