Only in 10th grade, IIRC. I had poor hygiene at the time, and hadn't been using deodorant yet. So, one day, after gym, I had to sit next to that chubby bitch type who makes a big deal out of things. I cleaned my act up rather quickly, but whenever I walked by her she would rather loudly be like, "That kid REEKS." Even through the next year. Probably the only person in my life I've ever hated.
In third grade, I told my best friend I liked a certain girl. When I come in from recess that day, the girl walks up to me and says she heard I liked her. I denied it, and nothing ever came from it.