The document summarizes how various children's books use different visual elements like line, texture, shape, and color in their illustrations. It provides examples from books like "Olivia", "Where the Wild Things Are", and "This is Not My Hat" to show how elements like line depict walls and frowns or how texture makes water and fur look realistic. It then discusses criteria like character, plot, setting, and theme and gives examples of how books demonstrate these through their illustrations.