Last week, SCOTUS struck down pupil assignment plans that focused on students' race. The goal of the plans was to achieve racial balance in the public schools. The opinion was really 4 - 1 - 4, and arguably Justice Kennedy's concurring opinion is controlling on lower federal courts. What we have with the plurality plus Kennedy is that Diversity is as compelling state interest for K-12--just like in Grutter. However, race may not be the sole factor in student assignment--it may be one of many factors when achieving diversity, which is not simply various colors of students in a classroom. Before school districts resort to looking at a student's race to accomplish the ends of diversity, they must first have tried race-neutral policies. For example, a school should not resort to race if it has not tried to balance class rooms by using socioeconomic factors (e.g., balancing classrooms based on the number of student receiving free lunch, etc.).
What we really see in this opinion is a split on the meaning of Brown. The conservatives interpret Brown as the death knell of state-imposed racial segregation, whereas the liberals read Brown as giving state actors license to racially balance classrooms even if there has been not state action causing the separation. Justice Kennedy seems to lean towards the liberals on this one. The next appointment to the Supreme Court, however, could change this balance.