Hello there, @krlynch 
Welcome to the Canvas Community. Thank you for posting your question. Unfortunately, this is not possible. However, there is a Feature Idea called https://community.canvaslms.com/ideas/3663-notifications-by-course that's open for voting. As you can see from that Feature Idea, it's a pretty popular request. So, if you feel that this Feature Idea aligns with something you would like to see implemented by Canvas engineers, I would suggest that you vote on it and consider posting a note in that thread letting them know why something like this would be important to you in Canvas. While I know this probably wasn't the answer you were hoping for, I hope it has helped to answer your question. Thanks Kaitlin.
