My experience with middle school students has fortunately been opposite to that of yours. I've had quite a lot of experience teaching in China also, and to be honest I've found the middle school children to be the most responsive. For example, I'm teaching at a private business college right now where only about 20% of the students will benefit by my teaching. The rest are completely without motivation or too tired from playing video games all night long. The little emperor and empress syndrome is rearing its ugly head in this situation. Mommy, Daddy, and Grandma and Grandpa have spoiled them so much that the concept of work of any kind is way over their heads.

Which brings me back to the middle school - literally actually because I will return soon to the same school. Those kids are largely from poor families and if they themselves lack the motivation to study, their parents will give it to them in the form of an ass kicking. So, my assumption is that the middle schools you've taught at have been in fairly affluent areas.

Now, as for my advice, I suggest a lot of dialogue work. Write interesting and relevant dialogues for your students to memorize. Remind them often that they will be tested after a certain amount of time and that their parents will see the results of their tests.(I grade their oral presentations on 4 different criteria.)These can be two person or three or even four person dialogues, but I wouldn't go beyond that or things can too easily get out of hand. The brighter students will spice up the dialogues on their own. The slower ones will try to keep it pretty simple.

Dialogues work especially well in large classes like mine. I had an average of 70 students in 9 different classes. Yeah, that's about 650 students to deal with, and as you can imagine it's a little difficult to personalize things with that many students. But with dialogues you can make the learning a little more real and personal.

As for charm, that's a whole other story. You're probably getting a little burned out after being here so long, but I'd guess that you're basically a charming person with many talents that you've set aside. Don't forget the performer that's inside of you and that you probably used to use quite effectively in your classes. I use juggling in my classes and because I've got the balls right there I use them in a variety of ways to liven things up. As you know, the attention span of young learners is not very long. I find that when I notice things bogging down if I engage the students in a friendly game of catch or show off a few tricks, everyone wakes up and in no time we can get back on track. However, I don't buy into the Bozo concept either. I probably wouldn't make it as a middle school teacher in Thailand; I'm just too serious of a guy for that.

But please remember that dialogues can go a long way as a learning tool. They are effective not just for introducing new vocabulary and language points, but also perfectly suited for pronunciation practice. Mix it up a lot by not just having students do the dialogue work - give everyone the opportunity to "perform" with you the teacher. This gives you lots of opportunity to model the language, thereby reducing the necessity of correcting pronunciation.

Good luck!