This article explores the perceived disconnect between informal and formal musical knowledge, through a focused case study which aligned students' informal knowledge with aspects of the formal curriculum. The upper high school or senior secondary student participants had a background in the creation and performance of popular and contemporary music, and already possessed well-developed informal and aural-based learning skills. Using a latter phase of Green's (2008) informal learning research as a starting point, the students completed two written tasks: a scoring or transcription exercise, and an analysis report using the music "elements" or "concepts" framework of the syllabus. Legitimation Code Theory (LCT), was utilised in the theoretical appraisal of themes emerging from the study. Employing one LCT dimension known as "Semantics," which explores the context-dependence and complexity of knowledge, a range of knowledge types were observed. These made visible points of connection and disconnection between the students' informal knowledge and the formal knowledge required to complete the tasks. The study highlights the limitations of informal knowledge as a sole basis for formal knowledge construction, but equally unveils points of connection between the two, important in informing teacher facilitation, and, much needed in curriculum reform.