Nancy E. Krulik (born Brooklyn, New York) is an American writer, the author of more than 200 books for chilren and young adults, including three New York Times bestsellers. She is best known as the author and creator of the Katie Kazoo Switcheroo book series, which has brought her to the attention of second, third, and fourth graders nationwide. She is often a featured author on authors.vidshadow.com where she talks about the Katie Kazoo book series and her experience with writing it.