The study identified university students' levels of motivation and engagement, perceived benefits, and challenges in Massive Open Online Course (MOOC). It used the mixed-method research design and involved third- and fourth-year English language students (n = 61) who completed the Content-based Instruction (CBI) -- MOOC offered by the Regional English Language Office, Manila, Philippines. The validated MOOC Learner Engagement and Motivation Scale (MEM Scale) was adopted to determine the learners' levels of motivation and engagement in MOOCs. A focus group discussion was also done to determine the students' perceived benefits of and challenges in MOOCs. Results of the MEM Scale show that the students had "upper-medium level" of motivation (x[bar] = 3.54) and a high "level" of engagement (x[bar] = 4.22) in the CBI -- MOOC. Also, the data revealed five perceived benefits of MOOCs: 1) "appreciation of the self-paced learning"; 2) "complementation to formal learning"; 3) "international certification"; 4) "provision of professional development opportunities"; and 5) "attainment of intercultural competencies." Generally, the students experienced five challenges while enrolled in the course: 1) "language barriers"; 2) "lack of social interaction"; 3) "digital divide"; 4) "time-related constraints"; and 5) "challenging course content." Given the benefits of MOOCs, higher education institutions (HEIs) are encouraged to incorporate open online courses in the learning experiences of their students. Further, it is recommended that HEIs extend available resources to participants to lessen the perceived challenges of MOOCs which could promote higher levels of motivation and engagement of the students in the courses.