From ‘HUH?’ To ‘AHA!’: Development and Validation of a Bilingual Workbook in Grade 7 Mathematics

Mathematics is often viewed as a difficult subject, particularly for students who struggle with language instruction. The lack of accessible and linguistically appropriate materials contributes to misconceptions and low performance. This study developed and validated a bilingual workbook for Grade 7 students to address language-related barriers and enhance understanding of mathematical concepts. Anchored on Cummins' Theory of Bilingualism and Vygotsky’s Sociocultural Theory, the study adopted a descriptive-developmental research design following the ADDIE model of the Research and Development (R&D) approach. A diagnostic test administered to fifty (50) students identified the least-learned competencies in Numbers and Algebra, which guided the workbook content. Moreover, the workbook was validated by five (5) experts (three Mathematics and two language teachers with master’s degrees), and evaluated the usability through five pre-service teachers’ thoughts. Findings revealed low mastery in competencies such as “describe the set of integers” (MPS = 28.4%), “identify the absolute value of an integer, and its meaning on the number line” (MPS = 31.6%), and “simplify numerical expressions involving integers using number properties and the order of operations” (GEMDAS) (MPS = 32.8%). The workbook received very high validity ratings in terms of content validity (OM = 4.77 ) and was very highly acceptable in terms of acceptability (OM = 4.74). Content validity analysis showed all 22 items were rated as valid by all experts, yielding a CVR of 1.00 for each item and an overall CVI of 1.00, indicating excellent content validity. Results from pre-service teachers’ thoughts also indicated very high ratings across all criteria for the workbook’s usability (WM = 4.60). Results affirmed that the bilingual workbook was valid, highly acceptable, and a useful tool for bridging linguistic gaps in Mathematics. The study recommends future experimental research to measure its effectiveness on actual learning outcomes and encourages its application across other subjects and contexts, while also suggesting further refinement, replication, rigor, reach, and relevance to ensure broader educational impact.