The Scarecrow is one of the smartest characters in the Oz stories. Second only to the Woggle-bug in raw intelligence, he is often the one with the clever solution.
He even got an Oz story with his name on it: The Scarecrow of Oz. It was adapted from a film made by Baum called His Majesty, The Scarecrow of Oz. More recently, there has been an attempt to make a computer-animated version of the story. It was on YouTube briefly, but all I can find now are teaser clips of partially finished animation.
(It may be that they're cleaning up the animation further, since Trot often got her eyes heavily shadowed which made her look odd. I'm crossing my fingers that they're recasting the Scarecrow voice. His voice was grating and sounded much like Snarf from the old Thundercats cartoon.)