In the K-12 curriculum, mathematics plays a significant role and is given specific attention. To keep up with the pace, teachers need have a set of teaching options, including not simply chalk talk but also other methods and tactics for gaining students' attention and imparting knowledge. Reducing the learning competencies by 60 the prescribed module may not be sufficient to the learners to achieve a variety of objectives and ideas or skills that our learners expected to master?s in mathematics. Providing supplementary material that anchor in MELCs to promote motivation, interest, skill practices and to fill the gap in the topics. This study determined the acceptability and effectiveness of supplementary material in intermediate mathematics in Duhat Elementary School, School Year 2021-2022. It sought to answer the following questions: 1. the level of acceptability of supplementary material in intermediate mathematics in terms of component with regards to objectives, content, language used and activity; 2. the level of acceptability of supplementary material in intermediate mathematics in terms of characteristics with regards to adaptability, appropriateness; aesthetic value and usability; 3. the extent of learner?s mathematical performance in the pretest and posttest in using supplementary material in terms of arithmetic skill, geometric skill and higher order thinking skill (HOTS) 4. Do the learner?s mathematical performance have significant difference in terms of pretest and posttest? The study's research design was quasi-experimental. Purposive sampling was utilized, which is a non-probability sample that is chosen based on population characteristics and the study's objective. The selected fifty ? eight (58) Grade 4 Learners of Duhat Elementary School are the one whose answered the pretest and posttest while the twenty ? four (24) teachers from Division of Laguna answered the survey questionnaire. All these learners are modular distant learning as their mode of learning. The findings revealed the majority of teachers who evaluated the supplementary material found its component which are objectives, content, language used, and activity to be highly acceptable and for its characteristics which are adaptability, appropriateness, aesthetic value and usability to be highly acceptable as well it indicates the usefulness of supplementary material to continue the education and motivates the learner to attain the desired competencies in mathematics. The learners scores in pre-test in terms arithmetic skills and higher order thinking skills got proficient, approaching proficiency respectively as same result in the posttest while the geometric skills got approaching proficiency on pretest and received the proficient in posttest. This indicates that the learner?s mathematical performance improved after using supplementary material despite of small scale of mean increase it shows improvement. The study shows that supplementary material affects the mathematical performance in terms of arithmetic skills, geometric skills and higher order skills (HOTS). Therefore, there is a significant difference between learner?s mathematical performance in pretest and posttest scores in using supplementary material.

Performance

Characteristics

Supplementary Material

Component

arithmetic skills

geometric skills

higher order thinking skills