CHICAGO (CBS) — Mayor Rahm Emanuel is speaking out again in strong support of a longer day for Chicago Public Schools students.

He is now asking, why wait?

“Let’s make it good for the class of 2011 and 2012,” Emanuel said. “It is wrong to give these kids another year of a shortchanged education when we know what’s right.”

The Chicago Teachers Union opposes the plan for longer school day, on the grounds that they would only get a 2 percent raise for working an extra 90 minutes. The union is slamming the City Council for voting unanimously on Thursday to extend the day.

The union says aldermen caved to pressure from the mayor, and sidestepped the issue of paying teachers for working more hours.

“It is unfortunate the City Council bowed to the pressure of a well-orchestrated propaganda campaign that has no scientific evidence to show that this will do anything to improve the quality of education in our neighborhood schools,” union officials said in a prepared statement Thursday. “It is shameful that not one politician stood up for our students and teachers who deserve better. A longer school day is inevitable but how will it be funded and how will it be planned?”

The nonbinding resolution in favor of the longer day carries no legal weight, but does urge the Board of Education to lengthen the school day “as soon as possible.”

Three schools – Skinner North Elementary, 640 W. Scott St.; STEM Magnet Academy, 1522 W. Fillmore St.; and Genevieve Melody Elementary, 412 S. Keeler Ave. – broke ranks with the union and agreed to the longer school day before the school year began on Tuesday.

Teachers at a fourth school, Benjamin E. Mays Elementary Academy, 838 W. Marquette Rd, voted to adopt a longer school day there on Thursday.

Meanwhile, U.S. Secretary of Education and former Chicago Public Schools chief executive officer Arne Duncan is a major backer of the longer school day. He is in Chicago Friday for a meeting at Schurz High School, 3601 N. Milwaukee Ave., with Mayor Emanuel, Gov. Pat Quinn, and current schools CEO Jean-Claude Brizard.

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