New reforms envision ambitious science teaching, which requires a set of knowledge and abilities beginning teachers may not have. To support learning to teach, a practice-based approach has been suggested. This study examines the pathways of four preservice teachers' learning of one science teaching practice, "supporting students to construct evidence-based claims", during a two-year practice-based teacher education program. Analyses uncovered similarities across the teachers' pathways such as growth in science knowledge for teaching. Differences also existed. For example, one preservice teacher struggled to support students to analyze the data, whereas another developed sophisticated ability to do so. These analyses highlight the potential of a practice-based approach and extend understandings of preservice teachers' learning. The findings have implications for teacher educators.