This research focused on Grade 12 students who participated in a Massive Open Online Course (MOOC) in Media and Information Literacy (MIL) during the school year 2022-2023. The study involved 259 learners from Talipan National High School – Senior High School and employed a quantitative method with a descriptive research design. Input data included the average mean, mean percentage scores (MPS), and mastery level of students. The process involved collecting data from a summative test, item analysis, and grades/ratings from the online course. The average mean scores before the MOOC were distributed as follows: ABM-30.22, HUMSS-31.76, STEM-4.52, and TVL-20.26. Meanwhile, MPS before the MOOC were as follows: ABM-60.43, HUMSS-63.52, STEM-69.04, and TVL-40.41. However, the average mean scores after the MOOC showed the following results: ABM-28.42, HUMSS-48.69, STEM-33.61, and TVL-33.61. Lastly, MPS results after the MOOC revealed the following: ABM-58.83, HUMSS-97.38, and STEM as well as TVL obtained 67.22 and 47.32, respectively. The frequency-percentage distribution of the mastery level in the 50-item test before the MOOC showed that 21 items (42%) were least mastered, 10 items (20%) were nearly mastered, and only 19 items (38%) were mastered by the students. Meanwhile, after the MOOC, only 17 items (34%) had been least mastered, and 13 items (26%) as well as 20 items (40%) had been nearly mastered and mastered, respectively. From the statistical data, the researcher inferred that the use of MOOC as a teaching strategy helped Grade 12 students improve their mastery level in MIL. This finding is supported by the increase in the number of mastered items (+2%) and nearly mastered items (+6%). Consequently, there is a decrease in the number of least mastered items (-8%). These findings will serve as the basis for enhancing the learning guide in MOOC
