Controversy in the classroom

My mother has been an elementary school teacher for over 30 years. I’ve always thought she was a fabulous teacher, except when I had to be in her class for half a year in grade 7...not 13 year old should even have to go through that type of trauma. Recently, my mom and I discussed that idea of introducing controversial topics to students. For example, such topics as adoption, gay marriage, racism, immigration, assisted suicide, etc. My mother is somewhat conservative and believes that talking about such issues can be very useful but that we need to be very careful about how we approach it.
I also think that it's valuable to expose students to novels and material that may be controversial because they can be a tool to bring up discussions on important and relevant social issues. Conflicts of race and class exist in our history and continue to persist today. If as teachers our job is to inform, then I don't think we can leave out information just because it's uncomfortable to deal with. We must obviously be sensitive to the beliefs and values of our students, but I don't think we do that by brushing touchy issues under the rug. Through open, honest and respectful discussions we can address difficult subjects and help students deal with their feelings regarding them.
As a history teacher I want to be able to openly discuss Canada's dark history-Japanese internment, Native residential schools,etc-as well the positive. If we want to relate our past to the present, it's important to provide the entire picture. Only then can we start to find some solutions.