Visiting MSR&#x2F;Bangalore I was shown a neat demo using very simple QRcode-like paper and image recognition. Basically, each student had a paper they could hold up. On the front was a simple QR-code (facing the prof and camera). On the back on the edges were 4 possible answers, something like A&#x2F;1&#x2F;YES, B&#x2F;2&#x2F;NO, C&#x2F;3&#x2F;MAYBE, D&#x2F;4&#x2F;DONT-KNOW. The student would <i>rotate</i> the paper so their chosen answer was on top, then hold it up. A camera in the front of the room would detect in realtime and display the results. They even had an augmented reality smartphone app that would cover&#x2F;highlight the students and their responses.<p>Oh, and the QR codes were per student, so answers could be tracked.