Developing a research-based rationale requires formulating a way of thinking about teaching. Rather than a casual, weekend effort, the creation of a complete rationale is a long-term enterprise that may last for years and may never be finished (and probably should not be). In this chapter, the authors provide the guidance of a number of teachers to help as you select and refine goals, identify roles for students and teachers, describe your desired classroom environment, select content to be taught, and formulate assessment models for your teaching practices and student learning.