Adjustable-speed drives based on multiphase motors are of significant interest for safety-critical applications that necessitate wide fault-tolerant capabilities and high system reliability. Although multiphase machines are based on the same conceptual theory as three-phase machines, most undergraduate electrical machines and electric drives courses do not cover this topic. Setting aside the analysis challenges addressed in state-of-the-art literature, undergraduate electrical machines and power electronics courses are a good opportunity for students to understand the main concepts underlying such electric drive systems. This paper presents an adjustable-speed multiphase drive system senior project for electrical engineering undergraduate students that addresses their attainment of the course's learning outcomes. Eight of the course's students were assigned to build the multiphase variable-speed motor drive system. From a pedagogical point of view, this paper describes the methodology of using a senior project to engage students through experiential learning of electric drive systems, which span disciplines such as electrical machines, control, power electronics, and electronics. Students acquire both technical skills and soft skills, which are evaluated through various assessment activities. A number of lessons for future work have been drawn from the experience of applying this project-based learning approach.