It will be quite a challenge.  Most schools want language teachers as the math and science can be done by locals.

If you know people or if  you see some of the classifieds here, they do on occasion have openings but they require a degree in that field.

Luck!

You have to be someone with teaching experience who also has at least a bachelor's degree in the field you want to teach. True international schools with foreign management that offer foreign diploma will usually require a teaching license from a western country. They pay kingly salaries, but you'd better be a damn good teacher! There are also a lot of Chinese run "international programs" which offer their own Chinese diploma and will hire you with nothing more than the proof that you have a degree in the subject you wish to teach.

Typically these jobs are full time (with 15-20 teaching hours and an enormous workload outside of class), and you'll be teaching for the express purpose of getting students ready to take AP/A-level/SAT Subject tests.

If you want to work part-time, I would suggest that you try to self-employ by offering tutoring in the field of your interest to students who are already in an AP program. The teachers at those schools are forbidden to charge for tutoring so most won't offer tutoring in the evening or weekends (we are overworked enough already). Many of these students, especially in bigger cities, will be interested in getting a foreign tutor to help them. There will also be a fair number of kids who aren't even enrolled in an international program but still want to take SAT or AP tests.

Keep in mind that you must have a very good grasp of the concepts in order to teach/tutor these types of courses effectively. These are college level classes. The schools will often admit students with little or no English ability to the course, or be unwilling to tell rich parents that their student simply isn't smart enough to master Physics C. That means that YOU will be blamed for their failure. So my advice, if you do get involved in this, is to document everything and be ready to use Machiavellian tactics against lazy/disrespectful students.

i just would like to know what maths is unless you are talking about math i think one requirement might being able to spell math correctly i could be mistaken but iam pretty sure you have to spell it right

Considering you said maths, you are probably from a European country, your breifness in your question tells me you are not from the UK, New Zealand or Australia, which means you are probably out of luck. As I started as a subject teacher in Politics and Economics, it requires a degree in the discipline you would like to teach. If you do not have a degree in the discipline you are wanting to teach, be warned, Chinese are wiz's at Math, Chemistry and Physics, you'd better be on top of your game

It's a great challenge for you to teach mathematics , physics and chemistry in China. The locals have great talents for that. You should do more research on it. Good luck

I'm a math teacher in China, and Tapwater's response above is a good explanation.  You will need to be properly qualified.

There is a demand for getting math taught in English, as students want to attend college in English countries, so to prep they take all English classes in high school.  It's not as in-demand as English teaching, but it exists.  Got my job by searching the jobs classifieds on this site with the search keyword "math".