In this story, people are compared to eggs. Like eggs, which can be prepared in many different ways, people come with many different traits and personalities. However, before eggs are cooked, they start out very much alike. They may be different colors or sizes on the outside but when you crack them open, they are all alike on the inside.
The story takes place in a diner where many very different diners (in this story they are actually depicted as animals to highlight their differences) come in and order "Two eggs, please." But they each order their eggs prepared in different ways, over-easy, hard-boiled, even raw. The diners notice the similarities and differences between themselves and their meal choices. The chef then notices the differences between the exteriors of two eggs and the similarities between the interiors of the same eggs.
The story itself is actually very simple and has very little text. But there are two levels of meaning contained in the story. The obvious message of differences and similarities will be easy for young readers to grasp. When viewed from just this superficial level though, the book feels slow-paced and simplistic. You have to read the book more carefully to get the deeper message of acceptance in a community of diverse individuals. Children will probably need an adult's help to understand this difficult concept.