Are you sitting down? Because the results of some recent studies might shock you. As The Economist reported recently, it turns out that cutting school budgets…hurts student learning. And all joking aside, though the connection might be glaringly obvious, the details are pretty interesting and point us once again toward the most important school reform.

After the Great Recession of 2008, state governments slashed funding for school budgets. They had to. The impact of those cuts was not distributed equally to school districts, however. More affluent districts could support their schools, but districts with fewer financial resources couldn’t. Lower-income districts have traditionally relied more on state funding, so the cuts hurt them worse.

We know that test scores and other school numbers only tell part of the story, but in this case, that part is sad. Studies of the post-recession funding dip found that lower-income schools cut “core activities.” They saw a drop in reading and math test scores, as well as a drop in graduation rates. As one study found,

A 10% reduction in spending per-pupil in all four years of high school reduced the likelihood of a student graduating by 2.7 percentage points.

What’s the solution? For one thing, state support needs to return. By 2015, most states had not returned to pre-2008 school spending levels. A more comprehensive fix will be to eliminate the cruel educational gerrymander that determines school funding by zip code. Instead of fighting for more charter schools and voucher plans, we should put our energy into unifying city and suburban school districts, bringing together students of different backgrounds and leveling out our current senseless feast-or-famine funding scheme.

Sure, you say, but politically such “redistribution” schemes are a dead letter. No affluent suburban voter would support them, and without that support it’s a no-go. Maybe not. Recent polls in Massachusetts and across the South find that large majorities support overhauls of their states’ school-funding schemes. It’s time to stop fighting about charters and start pushing for real school-funding solutions.