Juvenile fiction about space flight was one important way to build excitement about the space race. More importantly books about space flight both fiction and non-fiction were eligible to be bought using funds from the National Defense Education Act of 1958.
The Act's purpose, among other things, was to provide money to schools to update their libraries. This lead to publishers increasing their output of "relevant" space books.
Zimmerman, Naoma and Ruby Schuyler. Corky in orbit. Chicago: Reilly & Lee. 31 p. illus. 21 cm.
The fiction books all had very similar content. Similar to the "space monkey" books these would show children using the space flight technology.
Often you would also see children bringing their pets. Poodles and cats in space!
Letting children see themselves as astronauts was powerful at a psychological level. If they could imagine they could grow up to be astronauts they would be willing to learn the science needed to get there.