International schools generally follow the American standards of education, whereas the "Brit Foundation Schools" are exactly what the name implies. Make no mistake, however, most of the "Brit Foundation Schools" do offer a number of alternatives. The IB (International Baccalaureate) being one of them. Also, almost all of them provide the opportunity for students to enter American universities through entrance tests like the SAT and the ToEFL. The choice, of course, is yours.
have a look at this link for more info.
http://www.esf.edu.hk/index.html
as for the Int'l schools, there are other choices....