Quite a Transformation
Not everyone from your high school or college is going to remain the same forever. Even the quiet, shy and antisocial little girl may turn out to be a famous star in the future; you should never judge a book by its cover. It turns out that Janis Joplin was that quiet little girl in high school who ended up becoming a famous rock star.
Janis Joplin is one of the greatest American singers of all time, so being able to say your grandma was her high school teacher must be pretty cool. They might not be related, but still, it’s an amusing anecdote to share with friends. Especially the part about her being a quiet, anti-social girl.