First, as the instructor, you need to have the homepage and roster tools enabled for students. To do this, go to Control Panel, Manage Course Menu. Find the Tools area, click Modify, and make sure that the Homepage tool is available. In addition, under Manage Course Menu, find the Communications area, click Modify, and make sure that the Roster communication tool is available.
Now, students can log into your Blackboard classroom, click on the Tools button (or whatever you have chosen to name it), and then click on Homepage. There they see a template that allows them to create a small webpage and include a picture. Students can view classmates' homepages by clicking on Communications (or whatever name you've given to the Communications area), Roster, List All, then List All again. They will see a list of everyone in the class and can click on the name of any student to view that student's homepage (if one has been prepared).