This article discusses peer apprenticeship learning (PAL) as situated within networked learning communities (NLCs). The context revolves around the diffusion of technologically-mediated learning in Singapore schools, where teachers begin to implement inquiry-oriented learning, consistent with 21st century learning, among students. As these schools have in past practices excelled in performance-driven pedagogies suitable for passing examinations, redesigning curricular resources, assessment, and pedagogical practices towards inquirybased learning was not insignificant. These teachers required convincing and also significant degrees of apprenticeship. The authors document PAL in action for teachers' epistemic change occurring within networks of teachers from across schools. The article delves into PAL processes, expanding the theory (see Hung, 1999) beyond students to teachers and beyond dyad pairs to communities of teachers. Through PAL situated in NLCs, the article argues that epistemic learning can be diffused across schools, and is an appropriate scaling mechanism, seeing that teacher capacity to enact 21st century learning is key.