CHICAGO (CBS) — Mayor Emanuel is using the charter schools run by the United Neighborhood Organization to show how the Chicago’s Public Schools could give children more time – an additional three weeks — in the classroom.

The change at the UNO-run charter schools means thousands of Chicago students will be in the classroom for more hours than any other major school district in America.

LISTEN: Newsradio 780 Political Editor Craig Dellimore reports

Beginning Aug. 1, the schools will have 190 days of classroom instruction, up from 175 for the school year that ended Thursday.

Emanuel and his schools CEO, Jean Claude Brizard, were impressed with the plan.

“Our first day of school starts Aug. 1, not the day after Labor Day,” Juan Rangel, UNO’s CEO, said.

And once it starts, it’ll last for 190 days of instruction, far more than the 170 days in traditional Chicago Public Schools. Those public schools are actually open with teachers inside for 193 days.

“This is criminal, what we do to our kids,” Brizard said. “We have about 193 days schools are open, but only 170 days kids actually attend schools. I’m not sure what happens in those 23 days when the kids are not there that the schools are actually open.”

It’s called teacher development, which teachers here will now be doing day in and day out during the school year, rather than emptying the UNO schools of kids for teachers-only development days.

“This is doable. It’s possible in every single public school across the city of Chicago,” Rangel said.

Charter school teachers aren’t part of the Chicago Teachers Union, though they say their pay is nearly comparable.

On Thursday, the CTU accused the mayor and his schools chief of “proposing half-baked ideas in the press rather than sitting down with the people who spend their time in the classroom to come up with reasonable solutions.”

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