Elmo (and some of his Sesame Street friends) introduce the reader to animals starting with all letters of the alphabet. I was surprised that they even found 2 that start with "X". Book ends with items that the child can "seek" throughout the book.

Elmo and Ernie take a trip through the alphabet by introducing a menagerie of animals, one for each of the 26 letters, with colorful illustrations.
These sturdy board books with padded covers are the perfect small size for toddlers, yet still have pages exploding with engaging text and illustrations. -- GoodReads