Students within a course or organisation can be grouped. Once grouped, interactive tools and Blackboard assignments can be created specific to those groups. Emails can also be sent specific to users within the group rather sending an announcement which will email everyone in the course.
There are two types of groups in Blackboard, self enrol and manual enrol. Self enrol groups are used to get students to select which groups they would like to be in. This could be used as workshop time slots or similar. Students are enrol by the instructors if it is a manual enrol group. This could be done individually or use a batch enrol script.