Composition, listening, and performance are essential activities in classroom music education, yet conventional music classes impose unnecessary limitations on students’ ability to develop these skills. Based on in-depth fieldwork and a user-centered design approach, we created MOGCLASS, a multimodal collaborative music environment that enhances students’ musical experience and improves teachers’ management of the classroom. We conducted a two-round system evaluation to improve the prototype and evaluate the system: Improvements were made based on the results from an iterative design evaluation, in which a trial system was implemented. The system then underwent a second round of evaluation through a three-week between-subject controlled experiment in a local primary school. Results showed that MOGCLASS is effective in motivating students to learn music, improving the way they collaborate with other students as well as helping teachers manage the classroom. ACM Classification K...