Recently a student asked me for an answer to a question on an assignment she was doing in my ECG Assessment class. I tend to answer questions with a questions, so I asked her, “what do you think the answer is?” After some discussion she came up with a response. Which was wrong. And she replied, “just kidding.” She wasn’t kidding, and she didn’t know the right answer.
This was far from an isolated incident. When a student answers a question incorrectly in class or in conversations outside of class, the most common response is “just kidding.” I first noticed it years ago, mostly from female students. Now I hear it equally from male students. I even hear it from other “adults,” most recently when an acquaintance didn’t remember what grade my son is in—”just kidding.”
It’s as though being wrong is so unacceptable, it is turned into a joke. The message seems to be “I wasn’t wrong, I was joking, and I knew the right answer all along.” The problem is, most students who say this really don’t know the right answer.I worry that this lack of ownership will prevent students from identifying weaknesses and missing opportunities to fill gaps in their knowledge.
So, now when I hear a student say “just kidding” I say “no, you’re not just kidding, you’re just wrong, and that’s okay.” Then we work to find the correct answer.
Dr Parr Says... 
I realize this is quite an old post, but I was attempting to research this subject online and came up with almost nothing. I, too, am confused by the use of “just kidding” in place of “I was wrong.” Troublingly, I have witnessed it only in a business setting when customers asked me for files they already had and, after being informed of such, replied “just kidding, I found it/them.” No, you weren’t kidding … you were mistaken. That you had incorrect/incomplete information was not a joke, and at no point did you make the conscious decision to tell me otherwise in an attempt at humor.
Baffling.