Technically I failed 7th grade because I got an F in English and one other class. Not because I didn't know the work, but because I did know it and refused to do it again.
Went to summer school for English and, despite the teacher loving my writing, I still got an F 'cause I ain't too keen on doing shit I've already proven I can do with zero effort.
We moved to Detroit later that summer. When school started they tried to have me repeat 7th grade and I'll never forget my moms telling them "No... My son was in a gifted program. Look at the classes he was taking last year: Algebra 1 and 2, Computer Science, college prep Earth Science and Chemistry... What grade do your kids usually get those classes?" And I remember the chick telling her something like 10th and 11th grade. "So then if anything you need to advance my son to the 9th or 10th grade, right?"
They ended up dropping me in the 8th grade where I continued with my tradition of telling teachers they were wrong and proving it, not doing homework, and sleeping in class.