Kate Hall was born and raised in St. Louis, Missouri. As a child, she loved to read. After college, she received a Master's Degree in Early Childhood Education. After graduating, she taught fourth grade in a Los Angeles inner-city school and on an American Air Force base in Germany. As she read to her students, she wanted to write children's books herself. As being a teacher took most of her energy, she moved to New York and worked in publishing, so that she could write in the evenings. In New York, she met illustrator Jim McMullan. She married him in 1979. She began writing children's books, some of which were illustrated by her husband. She continues to write and she teaches at New York University's School of Continuing and Professional Studies. She has written about 75 books for children. McMullan's books have been named The New York Times Best Picture Books of the Year, have appeared on state library award lists, and have received the Parents' Choice Award.