Just Kidding! Eons ago, when I was in middle school, I had a friend that would say "just kidding" all the time. She would not only say "just kidding," but she would take her right hand (as if saluting) and bang it on her chest as she said the words, then bring her hand back out quickly. Before long all the girls in my grade were doing the same thing. I'm sure we looked and sounded like idiots, but everyone probably just shoved it off as "that awkward stage."
As time went on, "just kidding" went from "jus kid'n" to "Ka-in" and finally simply "CAN," and the chest thump got quicker and harder. We went from doing the "CAN" thing every once in a while to after every sentence and eventually we did the "CAN" thing after every other word. I bet strangers must have thought I had a weird tic or something. (Although I was not quite as bad as the more hyper kids- HA). I remember my sister and parents laughing at me and trying to mimic the new trend, but they just didn't seem to cut it like my peers.
Now that I am a parent raising kids, I can only imagine how irritating that would be...and to teachers? Oh my goodness! I bet we drove them nuts. Unfortunately, this trend went on for several years until we were ready to enter high school. Then my parents sent me to private school.