CHICAGO (CBS)– Chicago Public Schools middle schoolers are getting ready for their first day back at school.

Sixth through eighth grade students started back to in-person learning Monday.

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Kindergartners and first through fifth graders returned last week.

CPS is still having a trouble finding enough teachers for their classrooms as nearly 4,000 are staying remote. More than 400 teachers are taking an unpaid leave of absence.

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The district wants to hire 600 more substitutes and part-time staff.

On Monday, CPS is also asking families with high schoolers if they want to return to classrooms this year.

The district and the teachers union are meeting this week to talk about how to make that happen.

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“All elementary grade students that want an option for in-person, which is really good,” said CPS CEO Janice Jackson.

CBS 2 Chicago Staff