Wordpress
Rather than reinventing the wheel, I'm going to point you over to the Wordpress support pages.
The main questions you'll have will be answered in the customize my site section and the create content section.
Go to your Wordpress.com site, and add a folder, so it looks like this:
sample.wordpress.com/wp-admin
If there are questions you have about using Wordpress that I didn't cover in class, or that the Wordpress support pages are silent on, please let me know, and I can give you some help.
(And if there are enough requests of a similar nature, then I'll probably add something here.)
Wordpress.com
Wordpress is a fine example of a CMS, and I wanted you all to have a chance to play around with one so that you can understand how the HTML anc CSS work we're doing with static pages would translate into a dynamic site. There is no need to pay to upgrade from the free version!