A Commonwealth Court judge has set a trial date for a landmark case that seeks to overhaul how Pennsylvania pays for public schools.

The case, brought by plaintiffs including the William Penn School District in Delaware County, will tentatively be heard in summer 2020, according to the order Thursday by Judge Renee Cohn Jubelirer. Discovery in the case is due to be completed by October.

“We’re glad that we’re moving forward toward trial. We remain confident we’ll be successful, and hope the legislature will act promptly ... but we’re prepared to go forward,” said Michael Churchill, an attorney with the Public Interest Law Center, which with the Education Law Center is representing plaintiffs in the case.

Although Pennsylvania courts have previously dismissed challenges to the state’s school-funding system, the lawsuit by school districts, parents, and advocacy groups was revived by the Pennsylvania Supreme Court last year.

Originally filed more than four years ago, it accuses the state of failing to provide enough funding for public schools, forcing districts to rely heavily on local taxpayers. It also alleges that the state is discriminating against students based on where they live, because poorer communities have more limited ability to raise money through taxes.

A state formula passed in 2016 revising the way Pennsylvania funded its schools — directing additional aid to districts with higher-needs students and weaker tax bases — applied only to a fraction of what the state spends on education. The spending gap between rich and poor districts has grown in recent years, according to the plaintiffs.

And although lawmakers and Gov. Wolf have added money for schools in recent budgets, school district pension expenses have risen faster than state aid — meaning available money for classroom costs has actually decreased since 2013, according to the plaintiffs.

Lawmakers “could take steps to end the huge disparities in funding ... between rich and poor districts, and to increase funding for the underfunded districts,” Churchill said. The suit asks the court to force the legislature to take action.

Drew Crompton, a lawyer for State Senate President Pro Tempore Joe Scarnati (R., Jefferson), said that “in our view, the major fix was to do what we did a couple years ago" by forming a commission to evaluate school funding, passing a new formula, and implementing it.

“Clearly, this case is going to take a while,” he said.