The flipped classroom is a pedagogical model in which the typical lecture and homework elements of a course are reversed. In an inverted (flipped) environment, the students are spending their in-class time in collaborative activities as application/reinforcement to what they have studied in out-of-class lectures uploaded on the Internet. The study aimed to determine the effectiveness of the flipped classroom approach in teaching Grade 9 Science in Rizal National Science High School, Philippines. Using experimental method of research, utilizing pre-test and post-test in two groups, the experimental and control. The respondents were selected using purposive sampling. The students in the control were taught with concepts in class time in the traditional setting and homework was given consequently. In the flipped classroom, the experimental group received instruction at home or out of class time through videos uploaded in the Internet. Activities and assignments were answered in class time. The student data for this research project were collected through a student pretest and a student post-test.

Results show that the experimental group got higher mean scores than the control group. The results signify that the flipped classroom approach can be effective in teaching Grade 9 Science. This study recommends the use of localized and contextualized examples in the lectures if a parallel study will be conducted.