This is an awesome kids' book that I don't think many people know about. I read it as a kid, and I was really excited to rediscover it when I worked with a tutoring program.
The professor is an explorer who travels the world trying to find an example of each monster on his list of 26 (one for each letter of the alphabet), and the only one that eludes him is that darn Zipperump-a-Zoo. Will he ever find it?
Kids will have a great time searching through the book and identifying the monsters. (There's an index with all of their pictures and names inside the first couple of pages.) It's also a great way for beginning readers to practice their letters.
The story is cute, and a great one to read together. The pictures are absolutely amazing.