This month marks the 65th anniversary of Brown vs. Board of Education, the landmark U.S. Supreme Court decision that struck down racially segregated schools. Justices rightly ruled that “separate but equal’’ schools operated in violation of the 14th Amendment. Therefore schools for whites only or blacks only were unconstitutional because separate at that time was inherently unequal.

The ruling was historic; it marked the beginning of an era of intentional efforts (some court-ordered) to diversify classrooms and offer equal educational opportunities to black children. What’s more, when Brown was decided unanimously in 1954 by a court led by Chief Justice Earl Warren, it laid the foundation for many anti-discrimination laws and rulings, in the areas of human, civil and voting rights as well as housing, employment and gender fairness.

Yet during recent decades, America’s schools have been resegregating, as a recent UCLA Civil Rights Project study documents. Researchers found that the percentage of intensely segregated schools, defined as those where less than 10% of the student body is white, tripled between 1988 and 2016, from 6% to 18% of all schools.

In “a heightened period of racial conflict in our public life,” the report warns, deepening school segregation by race and class “are very high-stakes trends threatening the future.”

That warning is based on research that shows nonwhite and low-income students who attend integrated schools perform better academically and earn higher incomes — when (as Brown called for years ago) they have equal access to education under the law.

Even though the court said in 1954 that action should be taken “with all deliberate speed,’’ here we are, decades later, still seeking educational equality. Only now the problem is framed as an achievement or opportunity gap. Despite considerable progress since the 1950s, racial disparities today still have some connection to unequal treatment — not only in education but in housing, health care and other areas of life.

Since both the educational landscape and population have changed, promoting equity may not now be limited to the important value of integration. Schools and communities must employ a variety of strategies to narrow stubborn disparities between racial groups — especially those between whites and blacks, Hispanics and American Indians.

That’s a way to honor the legacy of Brown — keep working for its core principles of justice and equality.