Xperiment explores the question What is justice? Justice has always been controversial among philosophers because it is the glue that holds society together. Society needs leaders and laws. But what justifies one person telling other people what to do? This is a vivid question for children dealing with bullies, teachers, and parents, as well as for adults who vote in political elections. The Guidebook explores several of the most important and influential political theories ever written, which are reflected in the story about X and his schoolmates.The Guidebook is the manual for implementing Xperiment, but it is called a "Guidebook" instead of a "Teacher Manual" in recognition of the fact that the material within its pages may be of interest to the children themselves, especially if they are motivated to delve more deeply into the content. It provides a summary of the plot developments for each chapter, a philosophical basis for the key concepts of the chapters, discussion questions, and web links to videos for further exploration of the content.