Blackboard Best Practices recommend that you link to videos rather than upload video files to your course. Instead, upload your videos to YouTube™, Vimeo, or a separate media server on campus and then link to them within your course. Be mindful of intellectual property rules.
This is a two step process. First, you (or your students) will need to upload videos to somewhere outside of Blackboard.
For Elmhurst College, there are several options that are easily available:
Step Two is actually linking to the videos (from whatever source) into Blackboard. Blackboard describes linking to files from other online sources as adding "social media" or "mashups." Here is more information from Blackboard on adding mashups to different content areas:
Elmhurst College currently uses "Original Course View" so follow the instructions for that only, not Ultra.