Calvin Cambridge, who is played by Lil Bow Wow, is the main character who gets sneakers which give him the skills of former NBA player Michael Jordan helping him make 3 shots at a halftime show and get signed to the NBA team at the age of 14. Later he ends up getting adopted by his teammate Tracy Reynolds and wants to live a normal kid's life.

Jonathan Lipnicki also known as Murph is Calvin's best friend at the foster home. He is very small tough so he gets bullied. When Calvin makes it to the NBA Murph is always at the games to watch. At the end he thinks he will be alone as Calvin is getting adopted but he doesn't leave without him and gets Murph to get adopted with him.

Tracy aka Morris Chestnut is an NBA player on the Knights. He was told to look out for Calvin and make sure he didn't get in trouble. At first he doesn't like Calvin especially after he beat him in a 1V1. Eventually he starts to become friends with Calvin and meets Murph. Seeing that they did not have any family, he adopts them both, giving them a home. 

Ox, also played by Jesse Plemons, is at the adoption center where he has always bullied and been mean to Calvin and Murph. After Stan, who is the head of the orphanage insults him, he helps Calvin and even though he has always hated Calvin and did not get adopted, he enjoys Stan being fired and ends up being friends with Calvin.

Frank Bernard who is played by Eugene Levy is the general manager of the Knights which is the NBA team that Tracy plays for and that Calvin joined. He is a funny character in the movie and makes many jokes with Calvin about him being "too good" for the team.

Anne Merea who plays Sister Theresa is the teacher to the kids at the orphanage is quite strict especially for homework. She stated that if Calvin did not do his homework he could not play in the basketball game.