CHICAGO (CBS) —  Time may be running out for Chicago Public Schools and the Chicago Teachers Union to reach an agreement on reopening high schools.

CPS high school students are scheduled to return to in-person learning Monday, April 19.

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But the district and the union are still haggling over COVID safety issues including high school schedules, accommodations and a plan to allow teachers to stay remote if no students are in class during the week.

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Talks were still in progress Wednesday night.

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If the two sides can’t reach an agreement, teachers said they will stay home starting Wednesday.