How do I deal with two teachers in my son's school who are unfriendly and prejudiced towards Asians?

How do I deal with two teachers in my son's who are unfriendly and prejudiced towards Asians? Whenever I drive through the pick-up line in the afternoon, these two female teacher who man the traffic don't wave or smile back at all. One teacher almost always, chooses to stop my car, to let the pedestrians walk. I no longer think its a coincidence. Today was the same thing again and I don't know how to handle it. I can not think of any other reason why they would act this way. I don't volunteer in school, but my husband does. I am not over-friendly, a bit reserved. I don't think that's a bad. I have one more child to send to this Catholic school which means more of this kind of treatment. Do I just ignore them and act like its nothing to me?