Contemporary literature suggests that music education is stuck in a cycle of cultural reproduction in which music teachers and curriculum writers value Western art music more than culturally-diverse and modern, technology-saturated musics, and train the next generation to hold similar views. A MOOC (Massive Open Online Course) was developed to challenge music teachers’ worldviews and to develop critical thinking about the field. In this mixed-methods study, we analysed 18 months of qualitative and quantitative data provided by the more than 1,600 course participants in response to paedagogical ‘provocations’ to assess whether it was successful in prompting critical thinking and worldview change. We used three methods to interrogate three distinct datasets: basic content analysis of participants’ publicly written reflections, statistical analysis of peer marking and context-network maps of peer comments. Between-methods triangulation crystallised our findings. We find that through required peer-review of public postings, an online community of practice formed, that it encouraged teachers to engage deeply with new ideas, and engage in Critical Thinking. We find that those who had a disposition towards critical thinking in the early assessments responded most positively to the pedagogy of provocation and were consistently prepared to question their own worldview and practice.