Farren Actually, the book says that her and Chad have been friends since childhood, but that she skipped the eighth grade I believe. So it really is one of many mistakes in the story.
Meg She skipped a grade earlier in her education. She's been in the same grade as these people for a long time.
Elle Her friends are regular students that graduated regularly. She's the only one that graduated early. She just made friends that are a year older than her but are still in the same year as her.
Akya Her friends could have been in the same program as her. I am in a program where I will get my diploma two years before regular people, and all of my friends are the same. I know for a fact that she graduated a year earlier because I just read that part.