This study examines teachers' cognitive development when interacting with video ethnography, a form of video cases. It used grounded theory to discover embedded meanings and relationships that emerge from descriptive data collected from six teachers. Findings revealed the categories of cognitive activities when using video ethnography and teachers' progression in a cognitive development process through interaction with video ethnography. The study has implications in improving technology use in teacher development, production of video cases, and research on case-based pedagogy and other related areas.