Laugh at yourself, or your own culture, and you achieve the desired effect in spades. I’m an Englishman who spent several years in Wales, learned French at school, and German in Germany. Relating a few of my experiences shows them that I, too, have had to go through the hell my students are now experiencing.
Start with the longest place name in Wales and offer to let anyone go home who can say it:
Most will try. It breaks the ice, and if you can’t say it yourself you’ve established some common ground. I always make a point of erasing it from the board and saying something like ‘No way. Forget it. Impossible.’
Next, a few words of French:
Qu’est ce que c’est? translates literally as what is it that it is?, a ridiculously complicated way of asking what something is. The answer, of course, has to accomodate the male/female quality of every noun. I usually wander around the room pointing out that male student x is sitting on a female chair, female student y is standing on a male floor etc.
If that’s not ridiculous enough then let’s poke fun at the poor old Germans.
Du, Dich, Dir, Sie, Ihn, Ihnen, Euch - actually I don’t know all the words for ‘you’ in German but those few are bewildering and daft enough that they’ll get the message. If they don’t then tell them that nouns in German are male, female or neutral - and a beer bottle is more feminine than a girl!
“Aren’t you glad you’re learning English?”
If you wish you can go on to explain that English is a confused combination of French and German, with a bit of the old celtic thrown in, and that’s why it never makes any sense. Then they know that you know how hard this is for them, and they don’t feel bad about finding it hard.
After bashing your own culture (I include all of Europe as ‘mine’.) it’s probably OK to have a go at the Japanese, or even gently tease your students over some common mispronunciation. I often ask if anyone speaks any other languages and there’s usually someone who will try a bit of Japanese, Indonesian or whatever. Getting them - the class - to translate it to English is a fairly effortless way to start them down the right path.
Many of my colleagues will try to learn some Chinese from the students, both to show the way and to get the English translation from students who think they can’t speak English. I try to avoid it myself, but it’s usually good for a laugh.
Then we’re into learning English and I really piss off the PC crowd with a very simple method I call ‘making fun of Americans’. It’s especially effective when using an American text book, as everything is spelt wrong and/or mispronounced - at least to my mind. I try to be clear that there is no definitive right or wrong way, and that I’m not going to penalize them for using AmE but it’s a great way to get them to think about - and thus remember - the lesson.
For instance, should you pronounce the T in often? Most Taiwanese are taught not to, but some are more comfortable saying it the way I do. Having tried it both ways, and laughed about it, students will remember how to say the word without feeling self-conscious.
One of my pals from the states plays the reverse game and makes fun of pompous Brits who have to make English unnecessarily complicated. (All those U’s in neighbour, humour etc!) This has exactly the same effect, although it may lead to the SAS being sent to teach him the error of his ways.
Some (definitely not all) students start to actually have opinions about English and choose one or other style. I guess in a way it’s encouraging a form of discrimination, perpetuating stereotypes even, but at the same time it is encouraging them to pursue native english of one form or another. Personally I’m here to teach English, not to raise other people’s kids. If one of my students walks into the classroom and says “Yo dude, whazzup?” to my “Good morning, how are you?” I’m more happy than if he just says “Hello teacher” and falls asleep.