The Story of the World was written with the elementary student in mind, but you can use the curriculum with an older student by leveling-up the related assignments to be age- and development-appropriate.
The older student's interest changes from listening to stories and gathering information to finding the relationships between the facts and understanding the implications of the stories. Instead of doing projects to illustrate the stories, the older student works to understand relationships and order within and among the stories. Older students move from coloring pages and model-making to mapping the changes in political boundaries, creating timelines to show chronological order and relationships among events, and writing outlines to order and correlate the information told in stories.
Expect your older student to work more independently. So, for example, where you read aloud to your younger students; your older students read on their own. With younger students, you discussed the "Questions for Review" found in each chapter of the Activity Book; with older students, you ask for written responses (and to make this easy, you can get the questions already typed out, with space for the student to write a response in our Review Questions Worksheets; the suggested responses are in the Activity Book).
The Story of the World Activity Books include some of this instruction about Multilevel Teaching.
"The Story of the World series is intended for children in grades 1–4, but is often used by older students: Volume One is written primarily for grades 1–4; Volume Two for grades 2–5; Volume Three for grade 3–6; Volume Four for grades 4–8. The maps and many of the activities in this book are also appropriate for children in grades 4–8. To use The Story of the World as the center of a multilevel history program, have your older child independently do the following: Read The Story of the World; follow this with the appropriate pages from the Kingfisher History Encyclopedia ; place all important dates on a timeline; do additional reading on his or her own level."
For more book lists and detailed directions on classical education methods for both elementary and middle-grade students, see The Well-Trained Mind: A Guide to Classical Education at Home, Fourth Edition, by Jessie Wise and Susan Wise Bauer, W.W. Norton, 2016), available from Well-Trained Mind Press or anywhere books are sold.
We recommend The History of the World series (the books and the Study Guides), and other history books for the advanced student, starting in 9th grade or later. Both the reading level and the content require maturity.