Stolen Stapler
Several years ago, I had a student pilfer a stapler from my desk. I was pretty sure who did it but didn’t have any proof at the time. Another kid came up to me later in the day and told me that my assumption of who took the stapler was correct.
So, during my prep period, I simply looked up the kid’s locker combination in the database. I opened his locker, found my stapler, and stapled a post-it to the brim of his Chicago Bulls hat that said, “It’s not nice to steal”.
I saw him wearing the hat a few days later, and the staple from the note was still embedded in the brim. Story credit: Reddit / AZScienceTeacher