I do agree.. there probably isn’t anything that would be considered “international”, certified and approved in all countries. On the other hand, you can learn just about everything except degreed specialized professions (doctor, lawyer etc.), online at little to no charge. The list of classes and courses area endless.

The ultimate international syllabus would probably have to be the IB (International Baccalaureate: http://www.ibo.org) but you have to attend a school that has signed up to their programme (called an IB World School). There are 14 IB World Schools in Hong Kong and you can see the full list at: http://www.ibo.org/school/search/index.cfm?programmes=DIPLOMA&country=HK®ion=&find_schools=Find

You can’t get the diploma as an independent candidate, however you can buy the course materials, workbooks etc and follow their international syllabus as a homeschooler. That is what I am doing with a couple of their courses.

I think there are also such programmes as International A Levels but I have no idea the extent of the international aspect of their syllabus.

www.sonlight.com is inexpensive and can or can not be religious based, you choose the program.