Paul Sancya / AP

“It is bananas,” Senator Kamala Harris told the audience—members of the American Federation of Teachers’ Michigan chapter—gathered at Marcus Garvey Academy, in Detroit, on Monday.

“It is completely upside down that we currently have a system where the funding of a school district is based on the tax base of that community,” the Democratic hopeful vying to run against President Donald Trump in 2020 said. The line met with approving head nods and a chorus of agreement. “It’s just basic math,” she continued, on a roll. “The community that has the lowest tax base is going to receive the fewest resources, and by the way probably [has] the highest need.”

What Harris is proposing could dramatically restructure American education. Currently, about 36 percent of public K–12 funding comes from local property taxes, depending on the state and district, according to a report from the Lincoln Institute of Land Policy, a think tank that researches land and taxation. Only about 10 percent of school funding comes from the federal government, and every state has its own mix of state and local dollars to fill out the pie.

Harris says America needs to reform the way it funds its schools. The big question is how—and Harris’s remarks did little to illuminate the mechanics of this reform. (The Harris campaign did not respond to a request for elaboration.) Her comments come on the heels of her proposal to increase federal spending to boost teacher pay by an average of $13,500 and suggest an emphasis on education as central to her campaign’s strategy.

This is not the first time a Democratic presidential candidate has criticized America’s system for funding its public schools. In 2016, during a presidential forum in Iowa, Senator Bernie Sanders declared, “We have to break our dependency on the property tax,” and suggested that the federal government play an active role in ensuring equality; his current campaign site, however, like Harris’s, does not mention property taxes in K–12 funding. Similarly, Senator Elizabeth Warren said in March that “we’ve gotta use our federal-education laws to help supplement so we can get real money into our public schools K–12.” But she has not, so far, been as specific on her K–12 policy ideas this election cycle as she has been on higher education, for which she has produced a detailed overhaul plan.

In theory, even despite unequal property wealth, America’s schools should be funded with something of an eye toward parity, because of what’s known as the “foundation” model. Under this system, which several states employ, the state legislature ensures that each school district has an equal baseline; if the school system were a car, for example, the legislature would make sure it had four tires with air in them, and a working engine. The state might set that foundation at $8,000 of funding per student, and districts must assess property taxes to see how much of that they can afford to pay on their own. The state, then, covers whatever the difference would be.

A property-poor area—one with a lot of tax-exempt buildings, or a low property value—might be able to cover $1,000, say, and the state would cover the last $7,000 to get it to the minimum threshold. In contrast, a property-wealthy area, with million-dollar homes aplenty, might be able to cover $14,000 per student with property taxes alone. The state government would not, then, provide it with any additional funding. So even though the poor districts can’t fall below a certain level, the rich districts are nevertheless advantaged because they’re significantly above the threshold.

One further problem with foundation models is that they’re rarely fully funded, Carlee Escue Simon, the executive director of the National Education Finance Academy, a nonprofit focused on school finance, told me. That means that even when the threshold is $8,000, states sometimes match up to $5,000—below the designated minimum. Meanwhile, school districts that don’t need a match might still be able to cover a full $14,000 per student.

That’s where the reliance on property taxes becomes so unequal. Simon told me that it did not appear as if Harris was saying that property taxes should not be factored into funding public schools at all. If that were the case, it would be incredibly difficult to pay for any system of public education. It is more so the “then what,” she said. “Once the property taxes are collected, how are they distributed? That needs to be examined, and states should be held accountable for that.”

How could the federal government hold states accountable for that? Perhaps simply by ensuring that they’re hitting the minimum thresholds they initially set out to meet, and encouraging them to do so by offering some form of federal match on equitable public-school spending. “It’s important that the federal government makes sure that the states are honoring their obligation,” Simon told me.

Instead of creating a new matching program, the federal government could also employ some of the programs it already has at its disposal, Roxanne Garza, a senior policy analyst at the policy think tank New America, told me. The federal government could dramatically increase the budget of programs under the Every Student Succeeds Act, the law aimed at improving basic educational programs offered by state and local governments. “It just comes down to how we prioritize whether or not we care about equity,” she said. The government is willing to fund a range of other things—the military, a wall—she said; why not schools?

Such approaches, however, would undoubtedly run into the philosophical debate over who—or what—is fundamentally responsible for schools. As Simon put it, “There are people who think that our federal-level Department of Education is already pushing [the] boundary”—overstepping into what is fundamentally a state and local issue. Still, Simon said, “the states should be recognizing that there are property-rich districts and other districts that do not share that same level of wealth. And they should balance this out.” Harris nodded to the disparity; now it’s a matter of what she proposes to address it.

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