QR Codes and Scavenger Hunt

One of my workshops this week calls for incorporating technology into math.  I love technology.  Not that I'm all that good at it, but I'm not afraid of it, so I'm game.  I just learned about QR codes--you know, those funny boxes that have turned up on ads all over the place?  When you aim a QR reader on your smartphone at them, they take you to a website.  Thanks to Lori Elliot http://www.lorislatestlinks.com/ I learned how to make a QR code. 

First, go to URL shortener: http://goo.gl/

Type in or paste the website address

Choose shorten

Click on details next to the new shortened address.  You'll see the QR code!  (I had to scroll up.)

Copy and paste it to your document.

Then I discovered this website http://classtools.net/QR/  

You type in 5 questions with answers.  It turns it into a QR scavenger hunt.  I can picture using it for 3D shapes, or having the answers be room numbers.  What uses can you think of?