I'm a math teacher and I found this website very useful if you want your students to analyze something specific about China. http://data.worldbank.org/country/china. The website is very well organized. You can find data about life expectancy to population growth to how much money people make in a region or whole country. The website also allows you to compare other regions to China which maybe helpful to compare and contrast countries to countries if you like a project of that sort.
.