If you do a "secret student" in your class as a behavior management tool, reward the successful secret students with a brag tag! I choose a secret student for the day, or hall walk, or library visit, or whatever works for you. Then, after we have made it to our destination and return to our classroom, I announce who the secret student was and that they did an awesome job following rules, and reward them with the brag tag. If they weren't successful, I do not tell them who it was, but I remind them that we will try again later.
I have included a color version, black and white, and grayscale versions to use depending on how you want to print them.