Practical theories of teaching are critical for teacher effectiveness as they provide basis for their actions and choices of pedagogies, learner activities, and curriculum materials. This study explored the content of professionally unqualified practicing teachers' practical theories and the changes that occurred as they progressed through a school-based Postgraduate Diploma in Education program. Drawing on concepts around practical theories, qualitative data generated through interviews and photo elicitation from six professionally unqualified teachers in rural Zimbabwe secondary schools were inductively analyzed. Findings indicate that content of the teachers' practical theories gradually evolved and developed as they progressed through three stages in the program: (a) Survival or "self-concerns" where content was composed of mediocre pedagogy--relationship focus, lesson preparation and delivery, and classroom management; (b) "task-concerns," where content constituted effective performance of teaching tasks portrayed by thorough lesson preparation, learner-centered pedagogies, student assessment, lesson evaluation, collaboration, creating conducive teaching/learning environments, and teacher enthusiasm; (c) "pupil and teacher learning concerns" with content encompassing identification and handling of student diversity, student engagement, moving students from known to unknown, self-evaluation, reflection, and research. Data further indicate individualistic and dynamic nature of practical theories through the nonuniform elements of fully developed theories after completing the program. This article illustrates that emersion in practice can promote professionally unqualified teachers' understandings of and attendance to underlying principles of teaching/learning which enhances modification of their views of teaching and development of well-developed practical theories.