Social movement organisations and unions can be spaces of transformative learning in which organisers research, debate, create, and put into action frameworks for social change. In this article, I engage with themes from Aziz Choudry's writings to explore learning and knowledge-making within and through the United Caucuses of Rank-and-File Educators (UCORE) network. This network has brought together organisers from nearly thirty social justice caucuses from across the United States, fuelling the development of contemporary educator movements. Drawing on over five years of research as a movement ethnographer, I argue that informal and non-formal processes of learning and knowledge production drive the growth of the UCORE network and, with it, broader educator movements.