As a family, learn about and celebrate the many different cultures of the people who call America home. Find occasions for you and your children to talk with and get to know people from other racial and ethnic groups, as well as from other countries. Instead, read, play games, write letters, do craft projects, exercise, ect. When your children see you continuing to learn, they'll realize that learning is a lifelong pleasure. Finally, watch your language.
Children do, indeed, say the darndest things.