This study developed and validated contextualized supplementary worksheets in Grade 8 English at Matnog National High School, Matnog II District, Division of Sorsogon Province for the school year 2022-2023. The respondents of the study were the Grade 8 Bougainvillea students who utilized the worksheets developed in this study and 5 English experts who validated the learning material. The study employed ADDIE (Analysis, Design, Development, Implementation, and Evaluation) model instructional design in the development and validation of the materials. Moreover, this study applied CTL (Contextual Teaching Learning) approach and intertextuality for contextualization. The contextualized supplementary worksheets covered English 8; Quarter 2 under the Most Essential Learning Competencies (MELCs) on the following learning contents: Visual-Verbal Illustrations, Fact vs. Opinion: Opinion Marking Signals, Multimodal Presentations, Comparing and Contrasting Own Opinions, and Text Messages: Positive and Negative Tone Words. The validity of the contextualized supplementary worksheets was evaluated by experts using Expert’s Validation Sheet (EVS) adopted from DepEd LRMDS along with the following factors: Content, Format, Presentation and Organization, and Accuracy. The results of the pretest and post-test show improvement in the performance of students after the utilization of the material. The result of the t-test revealed that there is a significant difference between pre-test and post-test scores of grade 8 students in English before and after the utilization of the worksheets. Moreover, students regarded the contextualized supplementary worksheets as relatable and interactive learning material. This indicates that the utilization of the contextualized supplementary worksheets is effective in increasing the level of performance of the students in grade 8 English.