Monolingual (as opposed to multilingual) classes can present a problem for teachers because there is often no compelling reason as to why students actually have to communicate with each other in the target language. Sure, they have to speak English to the teacher but in a class of 30 or 40, it's just not feasible because, as we all know: Teacher Centered is Bad! It's hard enough for me, who pretends to speak a total of 0 Korean words to my students, but the situation is actually far more difficult for Korean teachers.
This post was actually brought about by talking with a Korean colleague of mine who teaches the same students as I do-the ones who are preparing for an internship in the USA. These students actually all speak English reasonably fluently, except that she told me in class, they just all speak Korean to each other and to her. I find this really bizarre because the students are actually some of the best students I've ever taught and are in no way lazy or apathetic.
Anyway, some tips I have to help deal with monolingual classes:
1. Set the expectations high. For high-level classes, I say that I expect 99% English. 1% Korean is okay if they need to ask your partner for a vocab word or clarifying an instruction or something. For lower level classes, I say 95-5.
2. Design activities well. Make it easier for students just to use English with each other than Korean. It takes some experience to do this well, but it's really possible.
3. Encouragement/positive reinforcement. Praise students who are making a serious effort to speak in English to each other.
4. I "rank" classes in group activities such as a survey. It's surprisingly effective, at least in Korea and it can definitely help turn a "bad" class around. I will write an arrow on the board:
terrible----------> good----------> excellent
At the end of the activity, I will rank the class. If excellent, I will say things like: I loved how you all spoke together 1-1, You all wrote your partner's answers in English, I heard almost all of you speaking in English.
If not excellent, I will give suggestions for how to improve. Something like: I heard many students just speaking Korea...that's a waste of time, we are here to improve our English.
For even more tips on handling monolingual classes, check out this resource: