This study aims to develop and validate the interactive game-based spelling supplementary materials for grade 4 learners to be used in teaching spelling in English class. This study used design-based research (DBR) leading to improved design interventions as well as improved local and generalizable theory. The study also used the Successive Approximation Model (SAM) for the systematic sequences of activities that can be used in the development of spelling supplementary materials. The participants were 19 Grade 4 learners in an elementary level and a validating team which includes research and English school coordinators to evaluate the evaluation tool. The researcher implemented the interactive game-based spelling supplementary materials for grade 4 learners which consists of interactive and engaging games; it was utilized to improve the learners’ spelling skills. In the pre-test, the result was moderate; after conducting and implementing the study, the result was very high. For the level of acceptability of the learning material tool, the result was very highly acceptable. The result shows that there is a significant difference in the pre-test and post-test on spelling acquisition. The crafted interactive game-based spelling supplementary materials for grade 4 learners has yielded positive outcomes and it is highly recommended and encouraged to be integrated in English class.