I avoid politics completely with almost everyone, not for fear of government reprisal but because it is like trying to have a frank, honest discussion about sex with a three year old.

For religion I make a big deal out of how  I'm atheist, but that Chinese Christmas is offensive and disrespectful to the religious and non-religious alike, so they don't make me wear a friggin costume or sing at the Christmas party. Same goes for easter and I try to make out All Saint's Day to be a bigger thing than it is to avoid halloween costumes ("dress as ghost hahaha").

I agree with the two topics mentioned as starting point.  Politics because I have found that whatever they know about Chinese History is extremely biased, like they single handle defeated Japan in WW II, and Japan surrender to them.  Religion because I can't see how you believe in Budda, and consider the Moon and the Sun to be Gods, and pray to them too.  Of course, I do not tell them my reasons, just say I rather not get involved.

I also steer away from any conversation about sex.  Their ideas and knowledge is so far behind western countries that really I can't have an intelligent conversation.  Like having sex during menstruation will poison the male and he will die, and the only way to get pregnant is intercourse and ejaculation inside vagina.  Oral sex, male sperm on female hand, then she begins to masturbate, got pregnant and has no idea how it happened.

I also avoid getting involved in any discussion on any subject matter related to which country is best in any particular situation

I don't think there are any taboo subject, you can try the subjects mentioned above and more but i agree with kchur and HappyExPat, some subjects are best left alone. 

As open-minded, intelligent and 'westernized' one of my Chinese friend seems to be, i've gone terribly mad trying to make him see reason about certain subjects. I guess that's the day it really hit me that no matter the level of education, the excellent foreign language skills and the numerous trips abroad and foreign friends, he is still Chinese and some of his opinions can't be changed and reasoned with. It's a little disappointing but you always find other subjects....

I don't know, I only talk to the young Chinese people, the ones that go to college here. And a few of them are interested in religion, although I can't say anyone I know (including myself) is into politics any more than in just a general sense. I guess the most taboo topic is sex. When I was their age, I knew about all kinds of things like that. My friends and I would joke about it, and honestly, I consider myself well informed, even if I choose not to do it yet myself. But these kids, they don't know anything. They can't even say the word, it's so taboo to them, worse than American high schoolers. Maybe if I was a guy...guys seem to talk about it more. But as a girl, talking to girls, this subject doesn't come up, unless someone I know mentions a girl she knows that did it. But it's all hush hush embarassment, even though it's not about herself.

Definately. Don't mention that Taiwan does not consider itself to be part of mainland China, because you are sure to get a look of surprise and shock. Don't mention Tiananman Square, because, again, you will get a look of surprise (for a different reason). I was blatently told not to mention these two subjects in public by a very good (westernized) Chinese friend and have followed her adivce to this day (ummm...except for now, lol).

In the class, I will not talk about sex, mainly because it is not my place and for the fact that 98% of the students I teach are college aged females and I would feel uncomfortable doing so. I will talk about politics and religion, but only in a historical context, making sure to keep my personal opinion out of the discussion, and always in the context of language.

I never present one idea or culture as being better than another, just different, and make sure to present two or three examples of how people think about various things. I encourage my students to become informed on a variety of subjects and to expose themselves to different viewpoints about the city, province, country, region, and world they live in. To be well rounded in knowledge.

So far, I'm still employed.

fleching

Personally, I believe that I am here to develop second-language literacy in small children and that it is not my professional duty to engage in political nor social re-education.  For those of us with classroom experience in our own countries, we need only to reflect on the norms at home.  I never engaged in political discourse in my classes at home; I did not touch upon sexual topics in my classes at home; I tried to keep my classes on a purely academic level as a teacher of literacy and not as a political commissar.

When in Rome, do as the Romans...it's an old adage for sure but it maintains a great deal of value.

With close friends, I will give my views on religion and politics if it comes up, but I dont go on about the politics here. They already know it and dont really care to hear it from someone who isnt from here and so not so much affected by it.

As for class discussions, I agree with a lot of the above posts. Sex can be an uncomfortable subject for many, so unless asked a direct question about it, I dont bring it up (they are adults).

And as Happy mentioned, avoiding topics about which country is better is a definite. You will sound either anti-chinese or arrogant or both.

However, occasionally you come across someone that does want a open and honest discussion about it. Those are the best, and I usually just let them lead the direction of the conversation and talk about their ideas. That way you get a good talk and you dont come across sounding all pompous or condescending (and being american, lots of people automatically assume i want to force my opinions onto others)

I think it depends on your personality. If you have shown that you can be fairly unbiased, intelligent, rational, etc, then they are more likely to listen reasonably. For instance, while we may discuss politics, I won't say that X country is the best, but may say that Y policy is more effective. Also, just because I come from the best land in the world, doesn't mean that it doesn't have faults that I'm blind to.

I think blind adherence to anything is the best way to destroy conversations - so showing unbiased attitudes is often welcomed, and promotes discussion. In that regard, I'm rather Socratic - ask lots of questions, get people thinking - don't give my opinions (whether it's here, or anywhere else in the world).