Only half of black high school students in the United States are graduating - says a report.
Little Rock, 1957: De-segregation defended by the National Guard
Researchers say that national high school graduation rates are failing to recognise the underlying problems facing black and Hispanic students.
While there is an average of 68% of students graduating from high school - the figure for black students is 50%.
The report comes 50 years after racial segregation in US schools was ruled illegal by the Supreme Court.
The anniversary of this Brown versus Board of Education ruling in 1954 has brought attention to how black students are currently faring within the state education system and whether integration has brought a more equal level of achievement.
But the report by the Urban Institute, a policy research group, claims there should be "grave concern" that so many students from ethnic minorities are still missing out at high school.
Black, American Indian and Hispanic students are all more likely to drop out without graduating than their white counterparts, it adds.
While 75% of white students and 77% of Asian students finish high school with a diploma, the figure for black students is only 50% and 53% for Hispanic students.
There was also a gender difference, with girls achieving much better results than boys.
The report argues that national educational averages should not be allowed to mask stark underlying differences between different student groups.
"This study provides the most compelling evidence to date that the nation finds itself in the midst of a serious, broad-based, and unrecognised crisis in high school completion," concludes the report.
This concern about the underachievement of black students follows research earlier this year which claimed that 50 years after the ruling to integrate black and white students, there was now a pattern of increasing "re-segregation".
According to the Civil Rights Project at Harvard University there has been "backward movement for desegregation in US schools, especially for Latino and African-American students, and particularly in the south".
Researchers reported "substantial slippage toward segregation" and large parts of the US where "most white students have little contact with minority students".