CHICAGO (CBS) — Several parent groups are questioning how the Chicago Public Schools can lengthen the school day starting next fall, without solid plans on how to use the extra time, or enough money to pay for it.

WBBM Newsradio Political Editor Craig Dellimore reports a coalition of parent groups spoke out in front of Mayor Rahm Emanuel’s City Hall office on Monday.

Jonathan Goldman, who has children at Thomas Drummond Elementary School, said the group Chicago Parents for Quality Education has compiled all the research on a longer school day.

“A lot of the information that the mayor and CPS have been putting out is just either misinformation that they are either unaware of, or that they’re deliberately using to mislead the public about this program,” Goldman said.

Goldman said parents support more classroom time for their kids, but most think 7 1/2 hours is too long. They prefer a 6 1/2-hour day, about 45 minutes longer than the current school day.

“I think that there is a consensus among parents across the city, and numerous surveys have shown that we need a day longer than (5 hours and 45 minutes),” he said.

LISTEN: WBBM Newsradio Political Editor Craig Dellimore reports

Wendy Katten, whose children are at Augustus Burley Elementary School, said CPS hasn’t shown it has the plans for how to spend the extra class time meaningfully.

“There are hundreds of studies that show that children need P.E., they need things like music, they need all of these things,” said Katten, co-founder of the parents group Raise Your Hand.

CPS officials defended their plans for a longer school day, saying it was about more than just more time in the classroom.

“This is about more than adding time to the school day – we’re strategically investing in initiatives that will ensure that additional time is quality time, and the result is to boost student achievement,” CPS spokeswoman Becky Carroll said. “Next fall, we will begin implementing the Common Core State Standards, which is a more rigorous curriculum that will better prepare students for college and career, as well as the new instructional framework, which will fundamentally change and improve the quality of teaching across the district. These initiatives, combined with the additional instructional time provided by the Full School day will provide both teachers and students with the tools needed to improve teaching and learning in every classroom.”

But parents questioned how the district could achieve the goals of the longer school day when it’s already running a significant deficit.

“There’s clearly not the budget, with the $600 to $700 million deficit, to provide all of these new (programs). Whether they can provide a few programs here and there, we know they don’t have the money to staff a full day,” Katten added.

Goldman said school officials should present a budget for the longer school day, noting in Boston and Houston, schools are spending an extra $1,300 to $2,000 per pupil to lengthen the school day.

“If you extrapolate those costs to Chicago Public Schools, we’re talking about between $500- and $800-million in new costs, in order to roll this out effectively,” Goldman said. “That’s on top of the $600- to $700-million deficit that CPS has already announced that they have. How are they going to make this work?”

The parents demanded a meeting with Emanuel to discuss plans for a longer school day.

In a statement, CPS officials said they’re making investments district-wide to give students more time in the classroom and a more rigorous curriculum.

“We share a deep commitment and passion with parents to ensure we are taking every step to boost student achievement throughout the District. These district-wide investments include giving our students more instructional time in the classroom, implementing a more rigorous curriculum to better prepare students for college and a new instructional framework that will improve the quality of teaching,” Carroll said in an email. “All of these will give principals and teachers more tools to help students achieve success in the classroom and beyond.”

The Chicago Board of Education has already unanimously approved plans to extend the school year by 10 days next year.

But the district has yet to explain exactly how it plans to pay for the longer school day or longer school year at a time when it is facing a budget deficit of $600 million to $700 million next school year. Officials have said that deficit could exceed $1 billion by the 2013-14 school year. The district is also negotiating a new contract with the Chicago Teachers Union, which is seeking significant teacher raises to pay for the changes.

The union has also repeatedly blasted the CPS plan for a longer school day, saying officials haven’t sufficiently explained how the extra time would benefit students or how the district would pay for the extra time teachers would be required to work.