Two years after it was first filed by education reform groups, a suit challenging the constitutionality of Pennsylvania’s education funding system has made its way to the state Supreme Court.

The lawsuit is a reminder that while Pennsylvania took a positive step in June, when lawmakers adopted a new funding formula to distribute money to school districts, systemic inequities and failures remain an issue.

The reform groups say the funding leaves poor students without books and computers.They are asking the state Supreme Court to declare the funding formula unconstitutional.

The suit has already been dismissed by a panel of Commonwealth Court judges who deemed that the groups were raising political issues the court couldn’t adjudicate. And justices on the state Supreme Court expressed the same kind of skepticism last week during oral arguments over whether they should take up the issue.

In our view they should allow the plaintiffs their day in court. At its core, the reformers’ case rides on the interpretation of a single phrase in the state Constitution: “adequate education.” The court has ruled in the past that justices can’t define what that phrase means, but this time the plaintiffs aren’t asking them to — they’re arguing that the state has already defined “adequate education” — and failed to live up to their own definition.

Is it adequate that Pennsylvania has the largest per-pupil spending gap between rich and poor districts in the country?

Is it adequate that more than half of the $10 billion in state funding for public schools each year goes to just 125 of the state’s 500 school districts?

Is it adequate for districts to be forced to rely upon a property tax-driven system that renders a student’s ZIP code the most important determining factor when it comes to education funding and opportunities?

Is it adequate that the state’s new funding formula — widely praised as a step in the right direction — only addresses how new education funding is distributed, not all funding? Or that it never actually asks how much funding districts need to meet state-set proficiency standards?

There are counter-arguments, refutations and justifications to the “no” reply that’s implicit in each of those questions. But to get to those arguments, you first have to allow the debate.

That’s what the plaintiffs in this suit are asking for, and it doesn’t seem out of line.

It took state legislators 18 months to agree on what has amounted to a minor package of school funding reforms. Perhaps a legal debate on the matter would prove useful in moving the ball forward.