Plugins

Courseware (documentation)
Courseware enables you to manage a class with a WordPress blog, including a schedule, bibliography, assignments, and other course information.

WPBook
WPBook works with the Facebook Development platform to create a Facebook Application (addable by users within the site) using a Wordpress blog.

In Development

Gradebook will allow you to manage and display your class grades securely to students, and hook into the Courseware plugin.