The purpose of this descriptive quantitative study was to address the spelling proficiency among high school students. The study participants were 39 seventh-grade students from Baltazar Nicor Valenzuela National High School. The study introduced an intervention called Digital Application Intervention to improve student spelling proficiency. The pre-test and post-test results showed a significant difference: the pre-test had a mean score of 24.49 (SD = 8.47), while the post-test showed a mean score of 43.56 (SD = 4.25). The statistical analysis revealed a significant improvement in spelling proficiency following the intervention, t (39) = 19.1 p<.001. Findings suggest that the intervention effectively improved students’ mastery levels. To provide a comprehensive understanding of the students' insights during and after the intervention, the researchers conducted interviews with selected individuals. From the responses gathered, five themes emerged regarding the insights of students: (1) deriving enjoyment and learning from spelling activities; (2) suggestions to make spelling activities more fun (3) consistent practice as a key to improvement; and (4) using various instructional materials and strategies as essential; and (5) being open for corrections and assistance from others. The positive impact of the Word Building Games was evident in improved recognition of word patterns, increased self-confidence, enhanced retention of word spellings, and a reduction in spelling mistakes. Both teachers and learners affirmed the strategy's ease of integration and its efficacy in providing immediate feedback. These findings underscore the value of research-based strategies like Word Building Games in fostering literacy development.