Your teacher behaved certain way not because she was white. But because she was ignorant, misinformed, biased, stupid, and racist. When you set up the argument between “white people” and “black people”, you are no different to racists who you fight against. You become a biased racist yourself. I am white, never lived in USA, my ancestors never had slaves. In fact, my ancestors have been enslaved by another white Nazi dude. And I am totally on your side in this argument. Social science can, and often is biased. And you should fight ignorance and misinformation. But, why would you judge me based on the color of my skin?