Here are a few ideas of things you could do that would count as OCB's for your class. If you need more ideas be sure to review Spector's OCB Checklist - it's linked in the 'What is an OCB?' section of this page.
In classes one of the things we see a lot as a professors is that many of you develop a relationship with the professor, but not so much one with each other. That's such a lost opportunity, especially when we're studying leadership, which by it's very nature requires people to act as a group or team. So that's why this is the method to gain extra credit in this class - We want to encourage making our classes more of a learning community, a bit more like we would be in the workplace (when we are all pursuing parallel purposes in a shared space), etc. Anything you can come up with which seems to work as an OCB you can turn in for points.