This action research examined the association between flash card interventions and improvements in mathematical performance among Grade 4 learners, specifically targeting multiplication skills development. Employing a quasi-experimental one-group pretest-posttest design, the study involved thirty-six Grade 4 learners enrolled at Ranao Elementary School during the 2022-2023 academic year. Data were collected through validated twenty-five-item pretest and posttest assessments focusing on two-digit multiplication problems. Statistical analysis using mean scores, mean percentage scores, and paired samples t-test revealed significant improvements in mathematical performance following the eight-week flash card intervention. Pretest results showed a mean score of 10.47 (41.9%) which increased to 12.92 (51.7%) in the posttest, representing a statistically significant difference [t(35) = -8.82, p < 0.001]. Effect size analysis revealed a large practical significance (Cohen's d = 0.98). The findings suggest that systematic flash card implementation is associated with enhanced multiplication computational fluency and accuracy among Grade 4 learners. This research contributes to evidence-based pedagogical practices in elementary mathematics education, particularly in addressing multiplication learning difficulties in the Filipino context. The study provides practical implications for teachers seeking effective, low-cost instructional strategies to improve basic mathematical skills.