Some say that multiculturalism isn't an issue in their schools because they don't have any students of color or students who speak other languages in their communities.
Some issues are just less visible.
For instance, people have strong differences of opinion in politics and religion. There are prejudices against some white ethnic groups. One of my neighbors is Polish American. She told her children not to tell anyone at school that they were part Polish because she didn't want them to be teased. These hidden diversities can be a springboard for people to think about the need for multicultural acceptance.