How should I deal with students making racist, sexist, anti-Semitic or homophobic comments during a class?
Briefly note the inappropriateness of the comment, point to the class ground rules (if it is appropriate) and move on with the lesson. If these comments persist, you might try making up a lesson on stereotypes and addressing the issue as a learning objective without targeting any individual. The goal is not to put a student on the spot publicly, but sometimes the comments need to be addressed somehow. A way to do this is to create some lessons around them.
How should I deal with students making racist, sexist, anti-Semitic or homophobic comments during a class?