Here are some of the websites I found talking about educational uses of QR codes:
Posted back in 2009. The most interesting example they listed to me was the "Test tubes with QR codes" entry.
Blog post from Duke's CIT
Basic overview of how they work and a list of some common examples.
7 ways higher education can use QR codes to connect with current and prospective students
Quick post by Noel Levitz around QR codes. Lists 7 ideas about how to use QR codes in academia.
For me, the self-guided tour of campus was the most interesting.
Use QR Codes for Flashcards You Can't Cheat On
Example of someone using QR codes as flash cards for learning a second language.