One of the best websites on contemporary Chinese demographics and agriculture is
http://www.iiasa.ac.at/Research/LUC/ChinaFood/index_m.htm
It was produced by Gerhard Heilig a few years back in response to Les Brown and WorldWatch's book Who Will Feed China?. That book argued that rising living standards and changing diets would combine with continuing population growth to dramatically increase China's overall food consumption. China would be able to purchase this food on the world market (now you know why farmers in Kansas favor free market policies and hate using food sanctions), but that poorer nations might be hard pressed to meet their needs.
Heilig has assembled a wealth of data and produced excellent charts and maps to discuss the current situation and the challenges China confronts. He concludes that China can feed 1.48 B people in 2025, even without technological improvements. He recommends, however, many important changes, including infrastructural strengthening and continued family planning.
This is a wonderful resource that high school and many middle school students would be able to use.
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