I recommend having an "Archive" notebook and associate the appropriate tags with each note. You can then create saved searches as necessary. It takes some up-front work, but it's well worth it. For instance, you could have some tags like: classroom-management child-psych project-ideas phys-101 phys-102 This article really helped me simplify my notebook scheme and helps outline a realistic tagging system. http://www.jamierubin.net/2014/07/15/going-paperless-how-i-simplified-my-notebook-organization-in-evernote-part-1/ In short: keep it in Evernote but keep it in an "Archive" notebook.
I also agree with GroupMonkey. 1. Select all notes from your Waterloo Physics 101 class (or whichever class). This will let you automatically tag all notes with tags of your choice. I agree waterloo_physics_101 makes sense. Then, move all notes to your "Waterloo" notebook (or a general Archive notebook). 2. Rinse and repeat for all other classes. 3. Create saved searches as necessary. I found this article to be incredibly helpful when developing a system for notebooks/tags. http://www.jamierubin.net/2014/07/15/going-paperless-how-i-simplified-my-notebook-organization-in-evernote-part-1