I've got some somewhere, but I don't think they did QR codes and they certainly didn't launch a link - that's what she enjoys. No idea why, but I'm not going to discourage her from anything that gets her interested in technology. We're going to get a t-shirt printed for her with a QR code saying "If found, please ring [phone number]".
First thought: this might be a neat Android game
Second thought: this has already been implemented