Chicago’s public school district will keep offering cash incentives to teachers and schools that add 90 minutes of class time to their school day.

The new STEM Magnet Elementary is one of three schools where teachers decided to take the controversial deal.

Today was the first day of school at the new STEM magnet elementary in the Taylor Street neighborhood. There were balloons, new shoes and mountains of school supplies.

Teachers here took a vote last Friday to make the school day longer. Now, instead of kids being here for less than six hours they’ll be here seven and a half.

On playground duty before school, third-grade teacher Blair Wagonheim says the teachers’ vote to extend the school day had nothing to do with cash incentives the district is offering.

WAGONHEIM: We did it because we felt it was what was best for our students. We really do have a unique curriculum that hasn’t been implemented in Chicago schools before, and to really do it correctly we just needed the additional time.

The new school focuses on science, technology, engineering and math—that’s what STEM stands for. Wagonheim says when teachers saw their schedules back in August, they’re the ones who asked the principal for more time.

WAGONHEIM: It puts more pressure on us trying to cram things into a very short day.

CPS is offering $150,000 to elementary schools if they agree to add 90 minutes of class time to the school day this fall. And every teacher in the school will get a check for $1,250.

The Chicago Teachers Union says that’s a bribe. Jesse Sharkey, vice-president of the union, says CPS didn’t like the answer it got when the union rejected a longer day for every elementary school. So it’s trying to negotiate individually with 482 elementary schools.

SHARKEY: You know with principals running around to individual schools saying, ‘There’s $150,000 on the line if you vote for this!’ I don’t know how else to characterize that. It’s pressure. It is a bribe. It’s irregular. The votes have been pushed through quickly without enough consideration on the part of the people who are going to be doing the work, and it’s a terrible way to run school policy.

In spite of such criticism, CPS says the financial incentives will continue. Standing on the street in front of the STEM school today, Mayor Rahm Emanuel urged teachers in other schools to follow the example here.

EMANUEL: I know one thing, the parents want it I know another thing the pastors want it. I know another thing, the public officials want it. And we’re gonna have it school by school until all our children in the city of Chicago finally get the length of day and length of year that they have earned. 

Parents still hanging around applauded. One shouted “Thank you, CPS!”

Behind the mayor, a retired teacher stoically held up a protest sign—it said “United we bargain, divided we beg.”

But parents like Mrs. Mei loved the news that their children would be in school longer.

MEI: She usually gets out at 1:40. So who’s a working parent that gets out at 1:40? Grandma is picking her up, but grandma cannot teach, cannot do anything except just leave them there. So there’s a waste of time basically from 2 o’clock to 6 o’clock. It’s four hours of wasted time.

Mei’s child will now get double periods of math and reading, and five extra minutes in every other subject. She’ll have 45 minutes for recess and lunch. Unfortunately for Mei, her other child goes to a different school and will still get out at 1:40.

CPS has been unclear how it will pay for its incentives. It would cost more than $70 million if the district gave $150,000 to every elementary school. The union says if CPS has that kind of money, it should have paid the 4 percent teacher raises called for in the contract. The union is considering action.

Meanwhile, teachers at more schools are expected to vote this week on lengthening their school day.