Heterogeneous classes are a frequent and complex challenge in university language departments, often creating difficulties for both learners and instructors. These classes, characterized by varying levels of proficiency among students, require innovative approaches to ensure effective teaching and learning. This study examines the potential of blended language learning, combined with differentiated pedagogy and a project-based approach, as a solution to address the diversity in multi-level FFL classes. To explore this, a three-phase action research project was designed and implemented, each involving a different group of multi-level learners and varying instructional formats. The first phase included doctoral students with beginner to intermediate proficiency, the second phase focused on Malaysian exchange students from engineering backgrounds, and the third phase brought together a diverse group of international students. The aim was to assess whether a blended learning system could effectively meet the specific needs of individual learners while maintaining the cohesion of the class as a whole. The findings demonstrated that the hybrid system allowed for personalized learning paths tailored to each student’s abilities and needs, all while fostering a sense of unity within the group dynamic. This approach highlights the potential of combining technology and pedagogical differentiation to effectively manage heterogeneity in language education.