Leo: Leo is the narrator of the book, or the one telling the story.  At first he thinks that Star Girl is strange and is going to be the topic of the year.  Leo and his friend Kevin have a talk show called the Hot Seat, this show is  for kids in his school who want to see what is going on.  But when the time comes to sign Star girl up for Hot Seat he backs down, but no one really knows why.  I  think that he is intimadated by her and he doesn't want to hurt her feelings if anyone makes fun of her.  But as the story goes on Leo realizes that it truly is a good idea to have Star girl on Hot Seat.  Eventually Leo has a strong interest in Star Girl, and ends up liking her very much.  After a while Star Girl feels the same way about Leo and soon enough they become a couple.  Leo has found the real person inside Star girl that no one else can seem to find.

Kevin: Kevin is Leo's best friend, and out of the two of them Kevin would probably be the more  adventurous one.  I say this because Kevin is willing to take the chance and have "Star girl" be the guest on Hot Seat.  He also wasn't afraid to be the host of the show, while Leo wanted nothing to do with being seen on T.V.  Kevin tries to change Leo's mind about showing Star 
Girl to the world. And soon enough he has changed Leo's mind about Star Girl in a huge way.

Star Girl: Star Girl has been said to be the weirdest girl at Mica High.  She has a totally different personality than everyone else.  She is always in everyone's buisness, but not in a bad way.  By this I mean she is always sending people cards and presents for very single  occasion, which includes marraiges, deaths, birthdays, making someone feel less lonely, and many more. She is also making every one feel good all the time.  At basketball games she would cheer for every team no matter what, she would play her ukele at lunch time, sing people the happy birthday song, and sometimes not even on their birthday.  At first everyone thinks that Star Girl was the best thing that ever happened to Mica high, but as time goes on everyone starts to realize Star Girl isn't really a "miracle" anymore.  People start to stop wanting to be friends with her, and everyone wants to kick her off the cheer leading team.  But even though Star Girl has been put down by everyone she doesn't get upset and she doesn't stop her daily routine.  Star Girl's personality is truly amazing.

Susan: Star Girl's real name. Star Girl has decided to become Susan again, because no one wants to be friends with her.  Susan is more of a "normal" girl.  She likes what every other Mica High girl would like.  She is more calm, and has a different personality that people start to like more.

Dori Dilson: Star Girl's best friend

Archie: Leo, Kevin, and Star Girl's elderly friend

Hilari Kimble: A popular cheerleader, that is a former friend of Star Girl