Racial diversity in United States schools is the representation of different racial or ethnic groups in American schools. The institutional practice of slavery, and later segregation, in the United States prevented certain racial groups from entering the school system until midway through the 20th century, when Brown v. Board of Education forbade racially segregated education. Globalization and migrations of peoples to the United States have increasingly led to a multicultural American population, which has in turn increased classroom diversity. Nevertheless, racial separation in schools still exists today, presenting challenges for racial diversification of public education in the United States.