US public schools are funded by a mix of local, state and federal money. Local property taxes make up a large share in many states, so school budgets reflect home values. Home values, in turn, reflect decades of redlining, segregation and exclusionary zoning.
In San Antonio Independent School District v. Rodriguez (1973), the Supreme Court ruled 5-4 that education is not a fundamental right under the US Constitution and that unequal property-tax funding did not violate it. That pushed school funding fights into state courts, where many lawsuits have since argued that state constitutions require adequate or equal funding.
The gap remains large. A 2019 report by the nonprofit EdBuild found that districts serving mostly white students received $23 billion more in state and local funding in the 2015-16 school year than districts serving mostly students of color. The two groups of districts served a similar number of children. Federal Title I money, created in 1965 for high-poverty schools, is too small to close the gap.