As a parent, you must stand up and speak for your kids and inturn speak for yourself. Write in the letter to the principle in a professional way and firmly says it is racial discrimnation, it is not tolerant and it is shock to be heard at classroom. If principle does not response, write to school board, it is so obvious the teacher is racist. As Chines show your "Zun Yan". "Su ke ren, he ke ren".