Object: This study presents a collective case study design and multi-method triangulation as a method for research on teachers’ knowledge and classroom practice, in particular the study of how in-service teachers view their teaching, and how teachers use practical knowledge and theories during teaching in the classroom.
Design/methodology/approach: This study used a multiple case study mixed method research in which the data collected, the categories and the interpretations were confronted using a mixed method triangulation procedure, with the aid of software for quality analysis (ATLAS.ti).
Findings: The relationship between teachers’ personal practice and theories on teaching offers a knowledge and understanding of some teachers’ vision about own teaching, formal and informal learning of teachers and how teachers use practical knowledge and theories during teaching in the classroom.
Originality/value: The research offers some useful suggestions about the methodological contribution for the retrieval and the analysis of qualitative data with a mixed method approach.
