As schools of education increasingly shift responsibility for preservice teacher (PST) preparation to school-based settings, the role of mentor teachers (MTs) has become central to the development of new science educators. Two related but distinct lines of inquiry address this shift. One examines reciprocity within the MT/PST relationship — the dynamic through which mentors and mentees mutually exchange support, knowledge, and skills (Cropanzano & Mitchell, 2005; Homans, 1971). Although no legal mandates require MT preparation, research consistently demonstrates that mentors who receive structured training report greater confidence and effectiveness, with corresponding benefits for PST learning outcomes (Parker et al., 2021; Ambrisotti, 2014; Hudson & Hudson, 2016). Without such support, preparation varies widely, creating inconsistencies that affect both mentor effectiveness and PST development.The other examines the role a structured community of practice consisting of mentors, PSTs, and master teachers plays in PST’s ability to engage students in science practices. The integrated analysis showed that strong, collaborative mentor relationships were a primary driver of gains in pedagogical content knowledge (PCK) specific to science practices (PCK-SP). At the same time, PST agency strongly predicted growth across all outcomes. The CoP served as a critical support structure, acting as a “third space” and surrogate mentor that provided access to collective expertise and experiential learning. This study’s findings support a practice-informed model utilizing “three pillars” for PST growth founded on collaborative mentorship, PST agency, and community structures. By aligning these pillars, teacher preparation programs can better equip new educators to enact ambitious science teaching, ultimately advancing equitable science education.
