You should sign up next to at least 3 topics as the class "expert" on that topic, at least 2 of which are associated with a week in class** (add'l topics at the bottom of the list). You should roughly follow the template shown in each category, and your entry should be properly sourced and include links for further information. Your entries should not be copies of Wikipedia. 

Confused? Here's How to Create a New Entry.

**[N.B. Week 1 does not count as "in-class", since it will not be associated with any in-class presentation.]