Hong Kong students’ declining motivation levels in learning music have become an alarming issue and a challenge for music educators. At the same time, while expressing an interest in popular music, local students have limited opportunities to study the genre as part of their formal school curricula. It leaves the question of what kinds of teaching strategies and music materials should be constructed to provide students with educational and musical values in the school music curriculum. The present study explores the effects and responses of implementing popular music education in the local classroom, examines students’ motivational levels and, the psychology of music learning based on the self-determination theory.A teaching approach was created based on the concepts from informal learning practices with the addition of singing elements, namely the Sing by Ear project. The approach is tailored to the Hong Kong classroom music context, as instruments and spacious practice rooms are not required when resources are limited. The project aims to provide a comprehensive music learning approach in which confidence, and satisfaction, and musicianship through listening, creating, and performing could be earned collaboratively and simultaneously with the activity. The current research was administered under the explanatory sequential approach, which involves two phases of data collection: a quantitative phase followed by a qualitative phase. By employing the convenience sampling method, 323 participants (aged 11- 14) were invited to the three-month project. Students were involved in singing cover songs by ear instead of reading music notations in an a cappella setting. A mobile learning strategy was adopted due to the enforcement of social distancing measures following the outbreak of the COVID-19 pandemic.Data were collected by pre-test and post-test survey instruments and student interviews to determine (1) the extent of self-determination for having formal school music lessons