My teacher called me the N word?

I am the only black person in the cl. I was sitting in my seat, diligently working away furiously, just doing what I'm supposed to be doing and one of my clmates began to blow in my face then threw their erasers and pencils, etc at me. Finally they snatched my book and paperts from me and yelled at them to me my stuff back so I could complete my work. My teacher began yelling at me saying I was a disgusting, pathetic N! I want to know if I can sue him for calling me such a filfthy name. I told the principal what he did but my principal said the teacher made a mistake. well, slavery and the fact that we don't get equal wages, houasing, employement etc were also mistakes and we have let those go for too long. I don't want to let this "mistake" go either. I want to sue him for all he's worth and make sure he's never able to teach again. This is the 21st century, we should all be tolerant and accpeting and respectful by this point.