Make your own QR code! Student work could be displayed in the hallway- each piece could have a QR code underneath and when someone scans it with a smart phone, it links them directly to a video of the student explaining the assignment.
Technology in the classroom: Start using QR codes in the classroom. This post has a link to a custom QR code app and many ideas of how to use them in the classroom, like having a math problem projected on the board for the kids to get.
The QR Code Treasure Hunt Generator will walk you through each step of creating QR codes for use in your classroom. The QR Code Treasure Hunt Generator also offers some examples of using QR code treasure hunts in classroom.