CHICAGO (CBS) — For the first time in more than 300 days, thousands of kindergarten through fifth-grade Chicago Public Schools students spent the day back in the classroom Monday.

As CBS 2 Political Investigator Dana Kozlov reported, the students are back in class – but not back to normal.

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The time since Chicago Public Schools grade schoolers were last physically in class amounts to two weeks shy of a year. For kindergartners, it is a brand-new life experience.

But classrooms were occupied with CPS K-5 students on Monday – as the result of a hard fought battle between CPS and the Chicago Teachers Union that almost ended in a teacher walkout.

“Quite simply, we are ready. We’ve been ready for a number of weeks,” said Patricia Davlantes, principal of Hawthorne Scholastic Academy at 3319 N. Clifton Ave.

CPS Chief Executive Officer Dr. Janice Jackson joined Mayor Lori Lightfoot and Ald. Tom Tunney (44th) at Hawthorne in the Lakeview community. Lightfoot pointed out CPS spent $100 million this school year to make buildings safe for in-person learning – part of the reopening agreement reached with the teachers’ union last month.

But Jackson said around 6,000 accommodations have been granted to CPS teachers – allowing them to stay remote – resulting in staffing shortages at some schools.

“We have deployed hundreds from individuals from Central Office out to these schools, and they will be there until we can, you know, ensure there is a replacement and make sure that the situation is stabilized,” Jackson said, “but we don’t have any schools that can’t open due to due to staffing.”

While K-5 students are back now, sixth through eighth graders are set to return Monday, March 8.

Next up is talks with the CTU about bringing high schoolers back.

“We’re going to have principals at the table; high school teachers at the table talking about what some of the challenges are so we can safely reopen high schools,” Jackson said.

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CTU President Jesse Sharkey said parents should be at the table, too. But despite the last acrimonious round of re-opening talks, Sharkey agrees there’s now a framework in place.

Meanwhile, also on the table this week are discussions between CPS and the CTU about getting high schoolers back in person too. Both sides said those acrimonious negotiations about reopening grade schools laid a framework – but there is still much to work out.

“I think that if we prioritize the hardest-to-reach students – that is the students who we haven’t heard from; the students who are failing – like, you know, we start with that,” Sharkey said, “and then we understand that pandemic school is not going to look just like normal school – if we can build that as a way to get high school going.”

“As far as the logistics on reopening, that’s going to vary across the district,” Jackson said. “There’s some schools were everybody could come back – you know, they’re underutilized. We can socially distance – do social distancing to a certain degree. But there are larger schools where it’s going to be much more difficult.”

As with the grade schoolers who chose to return, Dr. Jackson said it is now a goal of hers to get high schoolers back in person this year.

Sharkey indicated, though, that part of those discussions will include negotiating remote learning improvements for students who opt to stay home.

Dr. Jackson said almost 18,000 CPS staff have been offered the vaccine – but it was unclear late Monday how many had gotten one.

A new Board of Education rule allows CPS to ask that question, so she expects to have that number soon.

As for final staff and student attendance numbers for Monday, CPS had not provided that information late in the day.

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While some schools, including Hawthorne, preliminarily reported more than 50 percent of their student bodies returning in person, staff at another school said only 20 percent of students in total returned Monday.