We describe the recursive design process used to generate a nonsurvey introductory biology course built on a framework of evolutionary (social, sexual, natural, and nonadaptive) mechanisms, physicochemical processes and constraints, and systematic behaviors that shape all biological systems. The resulting narrative (based on a free text, Biofundamentals) and associated materials are described, and the ways in which they have been revised on the basis of students’ responses to drawing- and text-based formative assessments, interactive readings, and students’ response to exam questions are elaborated. Strategies to encourage student persistence through assessment strategies (such as “I know it now” tests) are described.