A taboo subject is one that may cause discomfort to one of the people in the class. This will probably only be an issue for adult and/or adolescent students. There are basically three subjects which some teachers would regard as taboos: sex, religion and politics.
While, as teachers, we thrive on communication in class, there are many other ways we can get our students to talk - and if they are particularly argumentative, there are plenty of issues that will leave students feeling they've achieved something without having had their beliefs challenged.
Many EFL teachers will be foreigners in their students' countries and may, in some cases, be the first or only contact the students will have had with other cultures, lifestyles and so on. Consequently it can be very tempting for both student and teacher to wish to sound each other out on certain aspects which may be considered either cultural or personal.
Although it's true that some people can get into pretty heated arguments about seemingly insignificant topics like a football match; discussions involving issues such as:
- religion (including religious education in schools)
- politics and related issues such as a particular case of sleaze, or a period of history
touch on people's fundamental beliefs and, as such, are almost guaranteed to stir things up, often among students themselves, but sometimes between the student and the teacher, however non-committal and neutral the latter's stance.
Nevertheless, if you are feeling brave, and you have a good prior knowledge of your students' opinions then these subjects can be most simulating.
Having said that, however confident you are of your ability to deal with group dynamics - whether in a one-to-one context or with a class - don't forget that what may have worked well in one class setting might go wrong in another.