The MC-squared project aims to design a new genre of electronic book called a c-book that includes interactive components, learning analytics, and collaborative design. As part of this project, a community of interest evaluated five c-books created by the community on various math topics to analyze their potential for fostering creative mathematical thinking. The evaluation found that most c-books used a mix of open-ended and closed activities sequenced intentionally to facilitate learning. Two c-books had a multidisciplinary focus, while the others focused more directly on mathematics. The c-books demonstrated potential for creativity in different ways depending on their goals and content area.