Blackboard Ultra Navigation includes a number of calendar enhancements that allows users to see activity across all of their courses in a single place. Clicking "Calendar" in the main navigation will open it and let you view appointments by Month or Day.
You can add events to your calendar by clicking the "add" icon in upper right corner.
Clicking the gear icon expands the calendar settings where you can control which calendars display. You can also add your own calendars from outside of Blackboard or create a "share" link to import your Blackboard calendar into your preferred application.
More information on using the calendar is available from Blackboard.