Different perspectives, pedagogies, pedagogic ideologies, musical backgrounds, and beliefs account for the challenges experienced by music educators in the Gauteng Province, South Africa, in implementing and enacting a music curriculum, especially in Music Magnet Schools. These challenges result in dissonance and tensions regarding music streams and teaching practices. Hence, the investigative process of this study focused on educators' knowledge in implementing a music curriculum in Music Magnet Schools in Gauteng Province. The research objectives of the study were to investigate educators' technological, pedagogical, and content knowledge of implementing a Music Magnet School Programme in the Gauteng Province. To understand how educators' technological, pedagogical, and content knowledge influence successful implementation of a Music Magnet School Programme in Gauteng. And to investigate why educators' technological, pedagogical, and content knowledge of implementing a Music Magnet School Programme in the Gauteng Province manifest itself in particular ways. Integrated mixed methods drawing from elements of qualitative and quantitative traditions were employed for this study. The rationale for employing mixed methods was to investigate the structured (what) and the unstructured (how) of implementing the music curriculum. The study's findings inferred that in their teaching, Music Magnet School educators follow the professional, societal, and personal propositions that later influence their teaching practices. Moreover, the findings showed that most participants were notable opponents of a pragmatic music curriculum. Thus, this article recommends the four propositions that could assist in deepening educators' understanding of several types of knowledge as an attempt to knowledge building.