She was known for designing the whole work: design, illustration, typeface, and space. She said first she made her drawings or preliminary sketches, then she wrote the story, as it came first to her in images. Her papers include the "numerous preparatory sketches, the reworking of illustrations that had not proven personally satisfactory to and the demands for quality reproduction of the artwork [that indicate her meticulous attention to detail." Her books were known for their themes of "importance of teamwork, environmental awareness, perseverance, and adapting to change while still recognizing the importance of the past."