Within each of your module sites you may be able to set up groups for your course-mates to sign up to. This may be beneficial when working on collaborative projects, sharing course materials, or organising and discussing course rep activities. Within a group you can:
set up a discussion board
email all group members
personalise a banner and channels (such as calculator and dictionary)
create Group Tasks
You can set up a group by accessing the 'Groups' item in the side menu of a Blackboard site. By selecting 'Create Group' you will then be given some options such as the name and desciption of the group, and the maximum number of course-mates who can self-enrol. When it has been set up you may wish to publicise the group to the students who you would like to sign up. However, when using this tool bear in mind that the group is not a private area and what you discuss and share in there can be viewed by tutors, who can also edit option such as availability of tools, and can add or remove group members.