CHICAGO (CBS) — Thousands of Chicago teachers have already switched back to in-person learning and thousands more are supposed to ehad back next week, but their union says everything from bad ventilation to a lack of vaccines is making it unsafe.

Teachers and parents met at Jungman STEM Magnet School in Pilsen. The Chicago Teachers Union is still locked in a battle with CPS over safety concerns. The union has said the district’s reopening plan is not safe, and said it will defend teachers who refuse to enter classrooms.

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“This is about: two weeks in the door we have over 50 COVID exposures, incidents, infections happening in school buildings. Anyone else would say time out,” CTU Vice President Stacy Davis Gates said.

CPS says public health data shows schools are safe enough, but CTU is demanding the district release the number of COVID-19 infections reported since the first wave of students and teachers returned to the classroom earlier this month.

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In-person classes resumed last week for pre-k and some special education programs at CPS, and teachers were required to be back one week earlier to prepare, but some teachers have refused to return to classrooms. CPS officials said teachers who don’t show up as required will be considered absent without leave, and won’t receive pay, or access to CPS email or remote teaching tools.

Students in kindergarten through 8th grade are scheduled to return for in-person classes on Feb. 1, and their teachers are required to be back in school on Jan. 25 to get ready.

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CBS 2 Chicago Staff