I love QR codes. I think they are just fun! I recently incorporated them into my Spanish 2 class. I had students choose a person or character, and write a paragraph to describe that person. They created QR codes with the answer to their "riddle".
Here is a photo of one of the creations.
We put them on a bulletin board in the hallway for others to read.
Here is a copy of the assignment and the steps the students walked through.