Kansas Statehouse in Topeka, February 2014.

Topeka ? Many Kansas legislators see their work toward complying with a state Supreme Court mandate on public school funding as unfinished even though lawmakers passed an increase in spending. Some expect to be forced to return to the Statehouse this summer.

Legislators approved a bill last week that phases in a $293 million increase in aid to the state’s 286 school districts over two years. Republican Gov. Sam Brownback has until June 19 to act on it and he and his aides haven’t hinted at his plans.

If the plan becomes law, the Supreme Court still must review it. The justices ruled in March that the state’s current education funding of about $4 billion a year is inadequate. Even lawmakers who support the plan fear at least parts of it won’t satisfy the court, forcing them to do more work later.

Here are key issues and potential consequences of the court’s review.

Is it enough money?

If the school funding plan becomes law, it will be challenged by attorneys representing the four school districts that sued the state in 2010. They don’t think the spending increase is big enough to guarantee that every child receives an adequate education.

Attorneys for the school districts have consistently supported a State Board of Education proposal to phase in an $893 million increase over two years — three times as much as legislators approved. John Robb, one of those lawyers, said the figure could be as high as $1.4 billion.

“This Legislature was woefully short,” Robb said.

No specific figure

But the Supreme Court didn’t say how much spending must increase in directing lawmakers to pass a new school finance law.

Its opinion also focused on helping the lowest-performing students, leading many lawmakers to believe that dedicating more money to programs for them is far more important than boosting total spending.

“No one in this building knows the right number,” said Rep. Larry Campbell, a conservative Olathe Republican and chairman of a special House school finance committee. “The most important thing is to get it over to the Supreme Court so we can find out if it’s the right number.”

Not just total dollars

Total spending is not the only issue. The education funding bill establishes a new per-pupil formula for distributing state aid that’s designed to ensure that poor districts don’t fall behind wealthier ones.

If there’s too much of a gap, the formula violates the state constitution.

Both Robb and Democratic legislators argue that the new formula provisions have problems.

For example, one allows districts to supplement state dollars by raising up to $1,482 per student through local property taxes. That’s easier for wealthy districts to do.

The bill calls for adjusting the amount annually to account for inflation. Critics will say wealthy districts will just see their revenue-raising advantage grow.

“There are some constitutional flaws in the body of the formula itself,” said Senate Minority Leader Anthony Hensley, a Topeka Democrat.

What if the court isn’t satisfied?

Kansas has been in and out of school funding lawsuits for decades, and in 2005 and 2016, Supreme Court decisions forced governors to call the Legislature into special sessions.

The court has said in the past that if the state doesn’t have a constitutional funding formula, it can’t distribute any of its aid — something that would shut public schools down.

But in their March ruling, the justices avoided making such a threat, and they have in the past given lawmakers time to make changes.

“They don’t want schools to be closed any more than we do,” said Senate Education Committee Chairwoman Molly Baumgardner, a conservative Louisburg Republican.