From Extended PLC Dialogue to Knowledge Forms: Exploring Expert Biology Teachers' Knowledge Development Pathway in the Sustenance of Inquiry-Based Science Teaching

Despite significant investments in science education reform, secondary classrooms struggle to implement inquiry-rich instruction that develops real-world problem-solving skills (Cohen & Ball, 1999; Bybee, 2013; NGSS, 2013; Ni et al., 2023). While Professional Learning Communities (PLCs) within improvement science frameworks show promise for sustained teacher collaboration (Cohen-Vogel et al., 2015), a disconnect persists between PLC dialogue/decisions and classroom implementation (Menekse, 2015; Takahashi & McDougal, 2016; Drayton et al., 2020). This qualitative study investigates how two expert secondary school biology teachers developed and enacted inquiry-based practices through their participation in an extended PLC initiative under the NSF-funded LIST Scholarship and Fellowship Program (Sunal et al., 2022). Guided by Social Cultural Learning Theory (SLT), the study addresses two research questions: 1) What knowledge forms emerge in expert biology teachers' PLC dialogues and decisions? 2) How do expert biology teachers apply PLC knowledge forms to sustain inquiry-based classrooms? Data sources included classroom videos, teacher interviews, and PLC meeting transcripts, analyzed through SLT constructs including replays/rehearsals, extensions, and single-loop-double-loop learning (Horn, 2010). Findings reveal critical distinctions in how shared PLC knowledge was interpreted and enacted. While both teachers demonstrated student-centered strategies, only one consistently embraced authentic inquiry characterized by delayed explanation, conceptual risk-taking, and leveraging student misconceptions. The other frequently returned to teacher-led explanation, illustrating how inquiry-based teaching is often conflated with general student engagement. The study highlights the importance of Reflective Knowledge Forms in supporting inquiry-based decisions and introduces the concept of epistemic participation—engagement that reflects a deep internalization of inquiry as a professional stance. Findings suggest that PLCs should be intentionally designed to support reflective, risk-taking, and conceptually rich teacher learning—however, further research is needed to confirm these results. Future research should explore how PLCs can be structured to recognize and build upon teachers' existing epistemic stances toward inquiry-based teaching — not as fixed positions, but as dynamic orientations that can develop through reflective practice and collaborative learning.