The Clark Doll Experiment, 1939

This was a test done for a Master’s thesis that involved children being presented with 2 dolls, 1 black 1 white. They asked the children which they would play with, which one is nicer/better, etc. The experiment showed a clear preference for the white doll. Some of the actual data is hard to find, but the work was accepted enough that the Supreme Court used it in Brown v Board of Education.