A digital whiteboard teaching demo using OneNote was posted on YouTube as part of the Caltech Adaptable Teaching Series.

You can also click here to view some notes about how to use OneNote as a digital whiteboard for teaching.  Some of the specifics are tailored to Caltech, but hopefully the notes are easily applied elsewhere.  Watch the video above for a description of the advantages of this approach, but a primary advantage is the ability to have all the notes be viewable in a browser window in real time.  In other words, students can "scroll back" and see what you wrote a few minutes ago.