Dr. Seuss's First Book was called The Pocket Book Of Boners. Although this may seem like quite an unusual name for a G-rated book, there is an explanation. Back in the day, a "boner" was a word used to describe a silly mistake.
Boner books were highly popular in the 1930's. This particular one illustrated by Dr. Seuess is about funny misunderstandings about the world that children have shared with their teachers.
From Wikipedia: "The Pocket Book of Boners contains 22 illustrations of boners(howlers, blunders), drawn by Dr. Seuss. The rest of the volume consists of short jokes and humorous observations with most being no more than four lines long. It is notable for being an early example of Dr. Seuss' distinct illustration style."
I need a copy of this book, not only because of the funny title, but the stories in it sound pretty entertaining too.