Which is considered a step in the move to end a racial caste system in the united states?

There are many steps that people took to end the racial caste system in the United States, but I think putting blacks into the schools was definitely a step in the right direction. ( I don't know if this what you wanted) Also, In India, there actually was a stronger caste system than in the United States but thanks to Muhammad Gandhi it now doesn't exist. He would dress up in the lower classes clothes and live in their villages which forced people to look at the lower class and to see what was going on around them.

The correct answer is :

The overturning of the "separate but equal" doctrine.