“Welcome to World Books are illustrated non-fictional historical books focusing on a Historical Character's era.

The books--generally titled Welcome to [Historical Characters Name]'s World: Year: Growing Up in [Era]—are large non-fiction books focused on each character's historical era. The majority of books were released in 1999. While some character events from the Central Series are interspersed and mentioned at the front (including reinforcing that the characters are fictional), the book focuses mostly on real data from the era, expanding on factual data and historical events and angles similar to the Looking Back sections.

Books often open with maps of a section of the continental United States or world at the time of the era, with the section relevant to the era emphasized. Photographs (from the era when possible), images of historical artifacts, illustrations, paintings, and historical facts are interspersed among the pages, along with paragraphs of historical events or vignettes. A single two-page spread tends to focus on a specific topic, such as the importance of church life to free African Americans. Diagrams and illustrations also include places such as housing and homesteads, buildings, and or maps of generic locations. For example, Addy's book has a diagram of a boarding house. The books also discuss less positive events of the era that are not heavily discussed in the series.

Books have extensive photo and illustration credits, stating where all non-series images and photographs are sourced from.

The last section of the book, A Peek Into the Future, theorizes the possible adult life of the character, including what they might have achieved or sought when older.

Welcome to Addy's World, 1864: Growing Up During America's Civil War, presents a look at southern plantation life and a northern city during the Civil War period, as seen through the eyes of nine-year-old Addy Walker who, with her mother, escaped from slavery and fled to freedom in the North.” (American Girl Wiki, 2023)