Sustaining Teacher Professional Learning in STEM: Lessons Learned from an 18-Year-Long Journey into TPACK-Guided Professional Development.

This article is a self-narrative of our 18-year research into the Technological Pedagogical Content Knowledge (TPACK)-guided professional development of teachers in ICT-enhanced mathematics learning. Using autoethnography as the methodology to elucidate our transformative personal evolution in implementing the TPACK model, we describe how we conceptualized and enacted the TPACK framework across three distinct phases of our research trajectory. In the first phase, our efforts focused on offering afternoon seminars and workshops on using educational software. Mathematics teachers attended the seminars and workshops voluntarily. In the second phase, we concentrated on designing programs guided by the principles of adult education, which emphasize the importance of learner autonomy and relevance, and socio-constructivist views of teacher professional growth, which stress the role of collaboration and reflection in learning. In the final phase, we adopted a systemic, school-based approach to investigating and expanding TPACK for mathematics and other STEM/STEAM teachers. At the end of each phase's description, we delve into the profound lessons learned and how these led to a paradigm shift, expanding our perspective on TPACK as practitioners and researchers. Finally, we present a set of recommendations for future research and practice aimed at facilitating the sustainability of STEM/STEAM teacher professional learning initiatives. [ABSTRACT FROM AUTHOR]