What is the theme in Rocket Boys: A Memoir by Homer Hickam?

Another theme in "Rocket Boys," is ingenuity. A boy with no ambition or knowledge of how to make rockets develops ingenuity and teaches himself to design, create and fly rockets. Sonny and his friends learn to cultivate inventiveness, creativity and resourcefulness. There are multiple occasions where Sonny and his rocket boys, must figure out how to obtain rocket components and ingredients to create rocket propellant. The news coverage of the launch of Sputnik piques Sonny's interest.