The study implemented and evaluated a TPDP for the sampled 106 STEAM (science, technology, engineering, agri-fisheries, mathematics) teachers. The study used participatory action research (PAR) as a methodological framework. Results reveal that in all phases of the TPDP, three key points emerged: power, product and process. Power emphasized equitable participation dislodging imbalance of power, while process highlighted PAR cycle: planning, acting, reflecting and discussing. Finally, the product: co-learners, and emancipated participants who co-developed lesson exemplars in STEAM. Results further reveal that the participants successfully crafted Lesson Exemplars in their chosen STEAM topic exemplifying the principles of TPCK (technological, pedagogical, content knowledge). Pilot tests (using Action Research) show how the STEAM teachers highly engaged the learners. As TPDP, PAR may achieve teacher quality and quality STEAM education in the country and may adapt micro-credentialing to fully structuralize capability building programs.