If the judge decides the case will not move forward, CPS officials have said they will end this school year 20 days early on June 1.
"The reason we are here is to prevent the school year from ending early. The reason we are here is to protect the education of the children in the city of Chicago. We're asking the judge to preserve the status quo, to protect their right to an education. That is what the civil rights statute was designed to do. After the judge rules, we'll know where we stand," said CPS CEO Forrest Claypool.
The judge's decision will come April 28.
Ending the school year on June 1 would save the cash-strapped district about $90 million, school officials said.
CPS is suing Illinois and Gov. Bruce Rauner, alleging discriminatory funding. CPS students make up 20 percent of Illinois students, but the district only receive 15 percent of state funding, Claypool said.
Claypool said this disparity discriminates against CPS, where 90 percent of students are of color, while the rest of the state districts are predominately white.
The district wants a judge to force the state to release more money.
"The effect of that funding is discriminatory against our children, who are primarily children of color," said CPS attorney Douglas Henning.
He said the judge has the power to end the discriminatory practice, but the state would determine how it would fix the disparity.
Attorneys for Rauner seek to dismiss the case.
Wednesday's hearing was a last-ditch effort to keep the school year going after a failed effort to get needed money from the city's Tax-Increment Financing (TIF) fund. CPS needs funds to pay for teachers' pension funds.
Parents, teachers, religious leaders and CPS officials packed the Daley Center courtroom Wednesday morning.