Aloof and isolated.
I had only one friend. I spent all my free time at school with him. We would talk randomly during recess and lunch. However, we rarely saw each other after class or during the summer, even though we lived maybe 300 m apart. For one year, I tried not to be with that friend because I wanted to meet new people, and I thought that if I only was with him, I would not meet anyone else. Result: I was alone entirely for one year.
Especially in grades 3 to 5 (14 to 17 y.o.), I talked a lot with the teachers, even those whose class I didn't like. I had good relations with them, I think.
I was very disorganized and disorderly. We always stayed in the same class and had a personnal desk with all our books, etc. Mine was always the most messy. I often forgot my books at home.
I was bullied, too. I would not say I didn't not care what the others thought of me (I would have rather preferred they not bully me), but the fact remains that I didn't try to please them, only not to antagonize them. I didn't care about clothes or anything, but then, there was a dress code.
I had decent grades, but I was in an elitist private school. I would imagine that I would have had top grades in a normal one. They varied a lot with the interest I put in any class. I had high grades in latin and history, and low ones in math and arts. There was no link between the effort spent and my grade, so I didn't study much (I still don't in college).
I faked sickness to avoid class several times, but mostly when I was late on projects or when I had a presentation to do, not because I didn't want to go. In any case, my mother was less credulous than the school nurse.