In an unprecedented move that hinges on a decades old municipal code, the Teacher's Union filed a lawsuit against the school system citing overcrowding.
A code passed in 1958 -- after the Our Lady of Angels School fire that killed 92 students -- requires that all classrooms have at least 20 square feet of space per body.
That means classrooms of 35 students and one teacher require at least 720 square feet of space.
The Union suit will include affidavits from teachers who have measured their rooms.
School officials say 90 percent of the classrooms in the CPS system are at least 700 square feet, and the typical classroom is 720 square feet.
"On top of the educational problems it would create, such huge class sizes would violate the city's health and safety codes in thousands of our classrooms," said Union President Marilyn Stewart in a statement. "So whether you look at it from an educational standpoint or a health and safety standpoint, what CEO Ron Huberman and his Board of Education are trying to do is unconscionable."
CPS estimates it can shave about $125 million off its budget by increasing class sizes from the maximum of 32 students to 35.
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