Teaching English in July in China

I would like to teach English in a summer school in July in China but it seems that just about all the organizations I can find that do this sort of thing are based in the USA and only want American or Canadian people. I am happy to volunteer my time and can pay for my flight to and from Hong Kong, but would want other expenses, like food, accomodation, travel within China met. Are there any organizations that want Australians in July and are my expectations of meeting costs reasonable ?