Brown vs The Board Of Education was over the matter of violation of the people's given 14th amendment rights. Because Korematsu vs US is over the same 14th amendment violation, they share a similarity.
The difference, however, is that in Brown vs Board they ruled that the segregation in schools was unconstitutional and therefore must not be permitted. And in Korematsu vs US most of the Supreme Court justices (with the exception of 3 dissents) thought that in this time of war that placing the people of a certain racial group in concentration camps was justified, for various reasons.
I really hope this helps!
