I love using QR Codes in my classroom- I use them for parent contact on Back to School Night, I have a QR code outside of my door that gives students my contact info (email only!) if I’m out of the room, and I have even used them at stations to allow students to open documents and digital resources and access exit tickets.
The catch, unfortunately, is that students do have to have access to a mobile device in order to read the code. At the high school level, this is not as much of an issue, but in elementary libraries, this may present some issues. I was able to pilot a program for iPads in the classroom two years ago, and my 10th grade students loved being able to scan the codes and have instant access to websites, documents, and forms online. QR codes are great for parent access to resources, too!
One way that I would love to use these in the library is to have students and parents request books that we don’t have. I created a Google Form for this, and linked it to the QR Code above. I would post the code and directions in the library, and students could request new books there. It keeps all of the requests in one spot, and makes them easy to sort by title, author, genre, or date, as all of the responses can be sent to a Google Spreadsheet. I love that I can cut down on paper usage too!