A Teaching-Learning Sequence on Introducing Aspects of the Control of Variables Strategy: Its Refinement Process

In this study we describe the refinement process from the first to the second phase of a teaching–learning sequence development and implementation. The TLS comprises several experimental activities that aim to support understanding of Control of Variables Strategy (CVS) reasoning in the context of floating/sinking and properties of magnets. The research was carried out during a science laboratory course in a department of early childhood education. The participants numbered 67 in the first phase of the survey and 45 pre-service early childhood teachers (referred to as student teachers) in the second phase. The analysis is theoretically grounded in Pickering’s model of scientific practice, as adapted in science education, which provides the analytical framework for identifying and categorizing refinement changes. The results showed that the refinements are differentiated from each other according to the factors that guide them. Specifically, the three refinement changes guided by the educational factor were local-guided, i.e., related to a specific activity dealing with the student teachers’ educational needs, and the other two, also driven by the scientific factor, were holistic-open refinements, i.e., related to a set of activities adjusting the TLS to the new scientific trends. These findings contribute to the literature on Teaching-Learning Sequence development by illustrating how theoretically grounded analysis can make refinement processes more explicit and analytically interpretable.