As a part of the Wallace Foundation’s Principal Pipeline Initiative, GLISI prepared a compilation of thirteen effective strategies, identified by principals for principals, designed to ensure the implementation of a rigorous curriculum in every classroom, for every child.  These strategies are organized within a Plan, Do, Check, Act (PDCA) framework, referred to throughout as “The Rigor Cycle” (p. 8). Within each section of the document, there are examples, resources, and tools aligned with the four sections of The Rigor Cycle that are in support of curriculum improvement.