Introduce yourself to other members of the course: who are you, why are you taking this, and what is the one thing that fascinates you most about human nature?
For instance, you could say:
My name is Michael Caulfield. I'm from Keene, NH. I am taking this course primarily for fun -- I've always been interested in this topic, and I read a lot of Educational Psychology in my work, but I've never had a full course on Psychology. So I'm looking forward to the breadth.
As far as what I find fascinating about humans -- I think it's the capacity for self-sacrifice. In events like Sandy Hook, or 9/11 you always find people who put themselves in grave danger to protect or save people. And often, the people that live to tell the tale they say that it wasn't really a conscious decision, that it just came naturally. I would love to understand more about that instinct, how and why we have it, and what causes it to kick in.