你学校有他们的道理, 这是很少的案例, 你可以试试

让他们看美中TREATY协议ARTICLE 19, 看你是不是适用.

http://www.irs.gov/pub/irs-trty/china.pdf

An individual who is, or immediately before visiting a Contracting State was, a resident of the other Contracting State and is temporarily present in the first-mentioned Contracting State for the primary purpose of teaching, giving lectures or conducting research at a university, college, school or other accredited educational institution or scientific
research institution in the first mentioned Contracting State shall be exempt from tax in the first mentioned
Contracting State for a period not exceeding three years in the aggregate in respect of remuneration for such teaching, lectures or research.