In the Jack and Jillian book series, Jack and Jillian write about learning, and creating, new things. When Jillian goes on safari, she writes about traveling to Africa, going on safari, the animals, how they live, and survive, on a nature preserve. The Jack and Jillian Book Series are aimed at encouraging, challenging young minds, and motivating them to remain active, both physically and mentally. Recommended for children 4 to 8.