The Berenstain Bears Fly-It! Up, Up, and Away! (First Time Books)

Illustrated in full color. At Bear Country Airport, Papa uses a balloon to demonstrate how a jet plane works.  Soon Brother, Sister, and their friends begin designing and making their own models.  The aerodynamic craze leads ultimately to Bear Country balloon-powered tournament and flying circus!  The Do-It! section explains how to construct and fly all sorts of balloon-powered jetcraft.