I try to teach as many Multicultural texts as possible. By teaching students about others, tolerance SHOULD raise. As for the students who fail to acknowledge the equality of every race (with rude and prejudicial comments), I simply remove them from the classroom. Prior to beginning any unit, I tell all of my students that nothing but respect will be accepted. If they fail to adhere to that rule, they will fail the unit.
Of these responses, I like #3's the best. It's the height of folly to suggest that the actions of a few reflect entirely on the whole. Individuals exist of all possible types that do not reflect their race, history, or upbringing.
As far as the OP, I would suggest a zero-tolerance position on any sort of racism, bullying, or other activity in the classroom. You cannot control what the students do outside, but while they are in the classroom they are students and you are the teacher. You have the power, implicitly granted by parents and the school board, to mete out punishment for inappropriate behavior. It seems harsh, but there is no room for leniency when it comes to racism. If you allow it to grow, or be seen as having no consequences, it becomes ingrained in thinking to the point where you can recognize it as incorrect and yet still believe it. I always say that racism is self-hatred because there is logically no such thing as race -- all human beings are of the same species. At the very least, I try to force people to admit that their hatred is based in something other than color, which does not and can not have bearing on quality of character.
When I was young, one of my teachers devised a way to divide our class into two large groups. As I recall, she divided us by eye color: those with darker eyes were in one group ("the browns"), and those with lighter eyes were in another group ("the blues"). We then flipped a coin to determine which group would be the dominant group and which the less-powerful group. For the next week, the less-powerful group was discriminated against in subtle ways by the dominant group. It could be that we even reversed the rankings at some point; I can't recall. In any case, that method made a very profound impression on me and taught me lessons I have never forgotten about how it feels to "walk in someone else's shoes." For all I know, such a method might even be forbidden today, and perhaps there are problems with it that I haven't thought of. In any case, that whole experience is one I definitely remember, if not in precise detail.
I agree that modeling and leading by example are great ways to promote cultural tolerance. I didn't teach about each ethnic group just for the sake of teaching it. If a particular culture was in line with the curriculum, we studied it, but not because I wanted to cover a particular culture. I did try to expose the students to many different cultures in the hopes that it would increase their understanding and tolerance of all cultures.
The main thing I did was to try to use everyday moments to teach cultural tolerance. Like post 2 said, most intolerance stems from ignorance and a general lack of information. The students knew I would not allow certain types of comments. If we came across one, I would use it as a teaching opportunity. For example, our school had a sizable group of Islamic students. While the other students had to wear clothing specific to the dress code, these students were allowed to wear their traditional robes and hijabs instead of the khaki pants and collared shirts. Our class looked at why they wore these and how it was important to their religion. I explained to the students that they didn't have to agree with the reasons or the religion but they did need to accept that other people believed in it. Several of the young ladies in class actually shared that they wished they could wear pants and a t-shirt like their peers. A simple, guided discussion put an end to a lot of the intolerance and quarreling in the classroom.
It's a fine line, not being artificial in manufacturing reasons to include a variety of backgrounds and viewpoints in discussions and activities but ensuring that other cultures are represented. I try to always have a diversity of examples in the back of my head that I can input as students are talking if the class responses are all coming from the same starting point. By making the comments low-key additions rather than beating the students over the head with the examples, hopefully they are heard and appreciated rather than immediately being dismissed as "teacher on her soapbox."
Above all, I always try to lead by example, showing no favoritism to people because of color or ethnic heritage. I taught for many years in a rural Southern area (in Florida), and many of the other teachers had a problem dealing with African-American students because of their own upbringing. I love to travel, and I always find positive aspects about other cultures wherever I go, and I try to bring this way of thinking into the classroom. There are always students that I take to more than others, but I never judge a student by his color or cultural background.
Modeling is great if it's genuine. But it needs to be done schoolwide to be effective. Kids don't just need an inclusive classroom, they need an inclusive school that they have ownership in. Recruit for Leadership roles and AP classes across the spectrum, and start in the 9th grade. What does the staff look like? Does it reflect the student population? They don't just need modeling, they need role models, and someone who lives inside their cultural perspective. I'm also very cognizant of who I call on in class, left to my own devices I tend not to call on Latinos as much because they tend to be quieter in class. So I consistently re-evaluate how I conduct a classroom.
I agree completely with the idea of modeling, but not with the idea of the "great people from every ethnic group" stuff. And it's not that I dislike people of color given that I am one... Students get completely turned off (at least at the HS age, which is what I teach) by the tokenism that textbooks use. "Oh, gotta say something about ethnic group X now to prove that they're as good as the white people." It's, in my opinion, demeaning to "minority" cultures to treat them like this.
I try to model tolerance, as the previous post advocates. Outside of that, I simply try to present all sides of any issue we're talking about. If we're talking about issues of poverty and ethnicity, I try to be even handed and talk about the possibility that the "dominant white culture" is to blame, but also about the ways in which the poor themselves might have a hand in their problems. I think that by looking critically at all groups we convey the message that all people are the same and that all people deserve to be subjected to the same level of scrutiny.
What a great question. Let me suggest a few ways.
First, you are actually in an ideal place to talk about tolerance with respect to all cultures, because you are in a position to educate. Since people learn from not only sitting under a teacher, but also by watching and observing, you will need to model tolerance. This is essential.
Second, since much intolerance is rooted in ignorance, you can teach several units on some of the great figures in history from around the world. In this way, students will begin to see people as people, who are just like them.
Third, you can talk about important social frameworks that challenge any one dominant worldview. What is commonsense in one place is not commonsense in another. By doing this, you can give a firm intellectual foundation on the practice of tolerance. Also you can emphasize the importance of diversity.
Fourth, you can have every students share about their backgrounds. The great part of doing something like this is that all people in America are immigrants, unless you are a native American. This exercise will show that tolerance was extended to them in some point in their family's life.