I'm working with a faculty member who is using a WordPress with his students this semester as a place for them to publish and reflect as a group. To make things easier for everyone involved, it's a good idea to batch create user accounts for the students so they don't have to go through that process (it's easy, but every step avoided means people are more comfortable and less aggravated with a service).
Do support that batch creation of users, I installed the "Import Users Plugin" which, surprisingly, provides a way to import users into a site. All you need to provide is a username and email address for each student and it will create the account, generate a password, assign the specified user Role, and send an email to the student so they can login. It doesn't create blogs for each student, but for our current use-case, it's ideal - adding users to a single blog in a WordPress Multiuser service.
If you need to batch create a bunch of users, first enable the "Dagon Design Import Users" plugin on your blog, then follow these instructions:
The list of users could be pulled from Blackboard or Peoplesoft, but needs to be reformatted into
username|email address
structure so the plugin can make use of it.