Here is some info from the Artistic Pursuits website…
I want to work from only one book, but my kids are not all K-3. What can I do?
Many parents with children in the K-3 grades and others in the 4-6 grades choose to use K-3 Book 1 as an introduction to the arts. Older students learn a lot about art history, are not talked down to, and really enjoy the projects. Once you know how easy the program is to use, you can then choose the following year whether to continue in the K-3 series with all students or to give the older student instruction in drawing and color principles as well, using the 4-6 Books. Many parents have the older students do both, going through the K-3 series together as a family and working on their own in the 4-6 Grade books.
If each set of books cover the same elements of art and composition, how do they vary?
The books vary on many levels. Each element and compositional term is examined in a different work of art as the Grades 4-6 look at American Art, Junior High look at art around the world, and Senior High look at European art. The How To page varies as each level is working with different mediums and technical aspects of making art. Grades 4-6 covers some very basic information that most students this age miss until pointed out. Senior High deals with techniques that would be more difficult for Grades 4-6 to understand. Grades 4-6 Books devote more units to the study of balance, while Senior High Books devote more units to the study of depth. Creativity exercises found at the bottom of the first page of each unit are different in every book, offering a vast variety of experiences through all three levels. Subject matter changes so that Grades 4-6 look at the element of shape in a cityscape and the project assignment is to draw from real objects like a collection of robots, car models, or doll figures. Junior High explores shape in a landscape with tigers and the project assignment is to draw a picture of an animal from a photograph. Senior High explores shape in a plant sketch and the project assignment is to draw a tree from direct observation. So the subject of shape is given variety and is explored in more depth as the age level increases.