Answer:
Brown v. Board of Education, 347 US 483 (1954)
The Supreme Court ruled that segregation in education was unconstitutional and that the African-American students could attend the originally segregated white schools. While this ended de jure (legal) segregation, the Supreme Court didn't outline the method for desegregation until Brown II (Brown v. Board of Education, 349 US 294 (1955), the following year.
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