Which potato chip is healthiest: (1) regular; (2) baked; or (3) sour cream and onion? This problem requires critical and numerical skills in order to read and compare nutrition labels. The question has applications in mathematics and science classrooms but also in teachers' lounges and school cafeterias. It is a problem that addresses the five process standards from the "NCTM Principles and Standards for School Mathematics" of problem solving, reasoning and proof, communication, connections, and representation, and it presents the perfect opportunity for a library lesson collaboratively planned with fourth grade teachers. The school library is the perfect place to explore mathematical problems. In this article, the author discusses the use of literature to build mathematical thinking. School librarians have long been familiar with integrating curriculum. Who is in a better position to broker connections with mathematics and literature, with data and critical thinking, and with mathematical questions across the curriculum and throughout the school? School librarians need to spread the word to mathematics educators that they will be strong partners in inquiry learning.