This article describes how the incorporation of a writing assignment, creating a book about culture and science, into the syllabus of methods science course for preservice teachers, was used to foster science content learning. Preservice teachers were actively and purposely engaged in science learning through the generation of a book about a particular component of their own culture. From this assignment they learned or mastered important scientific concepts and reflected about the need for differentiation. A significant outcome from this assignment is the awareness gained about the importance of cultural relevance in teaching science. Students expressed feelings of satisfaction about the learning experience as "seamless science learning" and wanted to use the same strategy to teach their elementary students.