A small majority of my Biology and Psychology classes 2000 level and above had text books

Most of those textbooks could get you in the B/C range for a grade without outside reading, the rest seemed like topical arrangements for the professor and nothing more.

Material for completing assignments was expected to come from primary research.

Programming classes all had master texts, as did foreign language classes that were phonics based. Topical foreign language classes (composition, conversation, etc) did not.