This dialogical narrative describes the observations and changes in instruction of an 8th-grade science teacher in an English language learner (ELL) sheltered science class before and after receiving instruction in ESL methods, and the backdrop for the teacher's growth, as narrated by the second language teacher educator who directed the teacher's professional development program. After receiving instruction in language acquisition theory, and strategies in teaching reading, writing, and listening to ELLs in content classes, the teacher's lessons were designed and conducted utilizing the newly acquired skills. The science teacher's transformation from content to content-ESL teacher was scaffolded via contemporary professional development models for ESL. Such training, it is argued, can provide content teachers the tools they need to work more effectively with ELLs in their classrooms. Narrative introspection can assist in reflective practice, as well as in meeting standards for professional development and licensure, for teachers and teacher educators alike.