The Chinese internal assessment is a written assignment which will be undertaken during your own time (at home).
First, you will need to choose a topic for your written assignment. The topic must come from one of the core topics, involving:
Communication
Global Issues
Social relationships
Health
Science and Technology
More information can be found here: http://xmltwo.ibo.org/publications/EAD/2011-en/guides/GR2-B_EN.pdf
You will need to select three to four appropriate sources. Appropriate sources can be websites, articles, journals or anything you find, but they must be in Chinese. Your teacher will be able to check whether the sources are appropriate or not.
A rationale of approximately 300 words will also have to be written, detailing your motives for choosing this topic. And of course, the written assessment must be completely in Chinese.