I got a D once. No, really, I was a mostly A student, but I wasn't so good at math and science (I love both now). Anyway, the science teacher had had my brother who's a year older and a scientific genius the year before. I think I was quite a disappointment. So, he was mad about that, wasn't a good teacher, didn't like that my gifted pull-out coincided with his science class (after all, I didn't seem gifted AT ALL to him!

), and would grade me poorly even when I did well.
We had to keep a journal. I always got a C. I asked one of the other girls to see hers when I heard she had a 100 on it. She had written all the notes very neatly, defined the words, and drawn full-color illustrations. So for the next 9 weeks, I very carefully rewrote all my notes in neat handwriting, defined and illustrated and colored every single night..........not an easy feat since I worked in my parents' business until close, drove 1/2 hour home, then did the farm chores. It was usually 9 by the time I could work on it.
So, turn in my journal, happy, and get it back with a C again. I showed it to the other girl and she said I should talk with the teacher as mine was as good as hers (this was one of the popular girls and I wasn't, so that was a big deal coming from her), so I screwed up my courage and went to ask him why my grade was lower than hers, when I had done what she had done. He said I cheated. I told him I had been there all but 2 class days, and he had told us to get the notes from someone else when we were out. Those were the only two days I copied notes. He said if I did it again, he'd give me a better grade. I asked if he would also change this one, and he said no.
I went home that day and told my mother that I was done with him, and would not be keeping a journal anymore. So I didn't. I did the assignments, took the tests, but did not turn in a journal, and got a 0. It gave me a D in the class.
I still remember her looking at that and getting so mad. She asked me why I had a D and I told her, "I already told you I wasn't going to do anything for him anymore. He hates me anyway." She was SOOOO mad!
That's the most rebellious thing I ever did. Not the wildest, but definitely the most rebellious.