so where does that place students of the health science faculty, who have a stash of old tests, assignments, and copy written notes only that can access?

each library (or the faculty library) has a storage of past papers available

Notes, if written by you in your own words (summarizing, etc) are your own property since you made them.

The part where students get into trouble is selling university property... ie. selling copies of tests/exams/course material, etc. If it was given to you by a professor, then most likely it is copyrighted and therefore making copies of it and selling it isn't allowed.

Sharing notes, however, I found to be useful when I was in university. Especially for courses where there was a lot of material to digest. Some people are really good at summarizing things, and getting their notes can be helpful.