The Rocket Boys of the title are a group of four teenage boys, including the memoir’s author, Homer Hickam Jr. Homer Jr. is called “Sonny” to distinguish him from his father, Homer Sr., who is a superintendent at the mine in Coalwood. Jake Mosby becomes a mentor to the boys and their rocket club.

Mosby is an engineer who comes from Ohio to work at the Coalwood mine, and Homer, Sr. is his supervisor. The older man is rather suspicious of the younger, college-educated engineers who are assigned there, as he places greater value on practical experience. Although Jake has some personal problems, including alcohol abuse, he has a keen interest in new applications of engineering, including rocketry. In addition to his own encouragement of the boys and their rocket-building project, he helps them get public recognition through a newsman friend, who writes about them in a local paper. Jake also has a telescope that he lets the boys use to stargaze, and he gives them math and science books. Furthermore, he provides them with financial support, which they ostensibly earn by washing his fancy sports car.