CHICAGO (CBS) — Chicago Teachers Union president Karen Lewis is reacting to plans that would lengthen the school day for Chicago Public Schools, suggesting the extra time could actually hurt some students.

As WBBM Newsradio’s John Cody reports, she said the object is to work smarter, not work longer. She says the system needs more teachers, teaching more subjects, not the same teachers just doing the same thing for longer hours.

LISTEN: WBBM Newsradio’s John Cody reports

Mayor Rahm Emanuel has called for lengthening the school day, and says he is not backing down.

But Lewis is rejecting the implication that Chicago teachers aren’t spending enough time in the classroom, as she scoffs at an idea that teachers should work a longer day and year.

She said the idea of having teacher doing more of what they’re doing now, and expecting different results, makes no sense.

She said some kids would even be hurt by a longer school day.

“I’ve had some students come to me and say – high school students say – ‘I have a job after school. Neither one of my parents are working right now. My job actually contributes to our family. For me to go to school longer, and for what,’ because they said that, ‘then that means that now I’m cut out of an opportunity to help my family,’” Lewis said.

Lewis said the way to raise test scores in Chicago is to hire more teachers, to focus on reading, art and music, and to cut the time teacher spent preparing pupils for standardized tests.

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