What is the most petty thing you've done toward a kid?

One of my students refused to participate in an activity, even after being asked to multiple times. He said he wouldn’t do it, and that he would fail rather than participate. After completing the activity, I asked him if he had changed his mind, and he hadn’t. That’s fine, however I do need a participation grade for you. This grade is based on what you did during the activity. He said he didn’t do sh*t. I then began typing on my laptop, and he asked me what I was doing. I just said I was putting in what he told me, and he wouldn’t let me write anything else. His participation grade is now “I didn’t do sh\*t”. I just thought that was petty enough to post here.<br><br>Edit: I feel like some of you didn’t read the whole post. I always give my kids second chances. I said I would let him change his grade if he changed his mind to participate. He wouldn’t, and then he told me what to write down as his grade. He also has a history of this behavior, and no one believes you when they say they refused to participate without any sort of proof.