I am also employed in "middle management" here in Thailand. "Middle management" in terms of rank, but as far as actually managing goes I'm pretty low end
I find myself feeling like a bird with no wings. I don't consider myself to have the educational background or experience to be managing a school particularly and I was pretty clear on this when I took the job, I do have training and experience in man-management and I was happy to take on an administration/motivational role. I wasn't surprised to find that the expectations placed on me are pretty low, I am not often asked to do anything above managing absence and general administration duties which is fine. I am however a proactive kind of person and have come up with a few ideas on improving performance and morale particularly, which is a big problem here, partly due to teacher's perceptions of the top management (often unjustified, but brought about by cultural differences mainly!) and partly because some of the teachers in all honesty aren't cut out for the job they are doing! My ideas, generally, are welcomed with open arms, debated, implemented in a weakened form and then forgotten about

I have at this stage, 9 months into the job, just about given up! Not particularly because I am angry with the management for their inability to do anything, or particularly because I am fed-up at the irresponsible atitude of a minority of the teachers that make problems for all (this seems to happen at almost all schools here from what I have seen and heard and is a by-product of poor management IMO). The reason I will quit at the end of the semester is because I just don't want to be doing a job where I am unable to do anything!
The Thai management don't help me but expect me to improve everything overnight and the farang staff want me to help solve their problems but are unwilling to compromise on anything

So it's been an experience, but not one I will be eager to repeat. I have a teaching position lined up for next semester and frankly I can't wait.