September 2023 ISSUE JESSAMEN D. SAMPERE, M.Ed, TEACHER 3 MANAYBANAY NATIONAL HIGH SCHOOL, PASTRANA DISTRICT DIVISION OF LEYTE, REGION VIII Title: EFFECTS OF GENERIC RECTANGLES (GR) ON GRADE 9 STUDENTS’ ACHIEVEMENT ON FACTORING POLYNOMIALS ABSTRACT Having mastery on factoring different types of polynomials is an important competency that helps students in understanding more about quadratic equations. Also, previous studies have shown that gaming approaches helps students improve their performance and achievement in different subject areas. However, research needs to show how gamebased learning help students improve their skills in factoring polynomials. Thus, this preexperimental research design specifically a one-group pretest-posttest research design sought to explore the extent to which the game- based mathematical tool called Generic Rectangle will significantly improve skills in factoring different types of polynomials particularly perfect square trinomial and general trinomials. The investigation was conducted last school year 2021-2022, every after-class hour 4:00- 5:00 in the afternoon which lasted for 5 days. A total of 72 Grade 9 students were purposely chosen to participate in the pretest and posttest on factoring polynomials. This study used a teacher-made test on factoring perfect square trinomial and general trinomials which have undergone validity and reliability tests. The data in this study suggest that there was a significant difference between the students’ performance on factoring perfect square trinomials and general trinomials before and after the respondents were exposed to the game-based mathematical tool Generic Rectangle as shown by the result of the dependent samples t-test. The researchers recommend that more training in localizing or indigenizing games should be offered by the Department of Education (DepEd), so that many teachers can create their own games with the purpose of improving students’ performance and skills. Keywords: Generic Rectangle, Factoring Polynomials, Perfect Square Trinomial, General Trinomials