Funding’s not the main reason for different outcomes in US schools, and probably not even a major reason. Considering all sources of funding, in some cities the struggling inner city schools have more money than a lot of the better-performing suburban schools (rural almost-always-poorly-performing schools, not so much)

Funding’s an easy target because it’s straightforward to fix, but we could even all that out (though, careful, or some struggling schools will lose funding if you simply level out who gets what) and the effect would be minimal.

Unfortunately, effective approaches to making real progress on that have little to do with schools at all. Stronger social safety nets and support, stronger worker protections, justice system reform, that kind of stuff. Hard stuff, where we lag behind much of the rest of the OECD and closing that gap at all is controversial. And many of the measures might take years and years to show up in improved test scores or what have you.