CHICAGO (CBS) — After agreeing not to lock out teachers this week as the Chicago Public Schools and Chicago Teachers Union continue negotiations on a deal for returning to in-person classes, Mayor Lori Lightfoot said Tuesday “I remain optimistic” about reaching an agreement.

“We have done a lot of work,” Lightfoot told CNN’s Alisyn Camerota on Tuesday morning. “Over 70 plus negotiating sessions with teachers, every day for the last two and a half weeks. We’re going to stay at the table.”

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The mayor said the two sides “made material progress” during negotiations on Monday, when she called for a “48-hour cooling-off period” in negotiations with CTU.

“We’re going to stay on the table so we can get a deal done that recognizes imbalances of the variety of issues, not the least of which is that remote learning is just not working for too many of our kids, particularly our Black and Brown students,” Lightfoot said.

The cooling off period means CPS students will continue learning remotely on Tuesday and Wednesday, and CPS won’t be locking out teachers who don’t show up at school buildings. CTU had warned teachers could go on strike if they’re locked out, but that’s on hold for now.

That gives them two days to come up with a final resolution that would give CPS parents an option to bring their children back to school or stay remote.

A statement late Monday from Chicago Teachers Union President Jesse Sharkey said the CTU and CPS would resume bargaining on Tuesday, as well as Wednesday.

“The mayor and CPS have announced a ‘two-day cooling off period’ and said they’ll continue bargaining Tuesday and Wednesday, as our members continue to teach and work remotely,” Sharkey said in the statement. “We continue to teach because of our members’ unity, their commitment to their school communities, and their fearless solidarity.”

Sharkey said in the statement that the CTU is not looking for a strike.

“We want to keep working remotely as we bargain an agreement to return to our classrooms safely. And we’re one step closer to that goal today, because management has agreed to stay at the table rather than escalating conflict or locking out educators,” he wrote.

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The mayor’s office has said the two sides have reached tentative agreements on five of eight key issues.

The three issues they’re still tackling include a vaccination plan for teachers and staff, remote work plans, and metrics for future school closures during the pandemic.

The union wants more concrete details on how CPS will offer and administer vaccinations for union members.

Meantime, while some teachers have been allowed to work from home even when in-person classes resume if they have an underlying health condition that puts them at greater risk from the virus, of if they care for at-risk relatives, the CTU said it wants added clarity on work-from-home policies.

Finally, CTU wants clear benchmarks on how and when CPS would close schools over future COVID-19 spikes.

Many parents have said the uncertainty surrounding reopening schools is frustrating.

“You’re not reaching a consensus. Why don’t we push the reopening for a week just so we know what’s going on, so we can have some stability, so we can talk to our kids, so we can be prepared for it,” Kate Jablonski said.

What’s not clear is just how many teachers who were required to report to schools on Monday failed to show up. They won’t be facing any consequences for now as remote learning and negotiations continue.

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