The Case of the Falling Sky — John R. Erickson

When Hank hears a rumor that the sky is going to fall from the ranch's resident rooster, he is naturally a bit skeptical. But then a report from Pete the Barncat and a strange dream seem to support the theory, and Hank realizes that he'd better take the threat seriously! So Hank decides that he'll do whatever it takes to prevent the sky from falling on his beloved ranch. Even if it means getting into trouble with Sally May (again)...