This action research aimed to enhance the science vocabulary acquisition of Grade 3 learners through the use of Augmented Reality (AR) flashcards. Conducted at Maniki Elementary School SPED Center in Kapalong, Davao del Norte, Philippines, the study addressed the observed difficulty of students in understanding and retaining science terms, particularly in topics under Earth and Space. A total of 30 students participated in a four-week intervention that employed interactive AR flashcards with digital 3D visuals and auditory components to reinforce vocabulary learning. The intervention was carried out during the National Reading Program (NRP) period through structured 30-minute sessions integrating visual interaction and vocabulary drills. A pre-test was administered to assess baseline performance, followed by AR flashcard sessions, and concluded with a post-test to evaluate learning gains. Quantitative data were analyzed using descriptive statistics and paired-sample t-tests. The results indicated a significant improvement in students’ performance, with mean scores increasing from 59.56% (low) in the pre-test to 91.33% (very high) in the post-test, t(29) = [insert t-value], p < .001, Cohen’s d = 6.89, indicating a large effect size. In addition, qualitative data from interviews with seven students supported the quantitative findings. Learners reported that AR flashcards made science terms easier to understand, increased engagement and confidence, and encouraged independent learning. The study concludes that AR flashcards are an effective tool for improving science vocabulary among elementary learners and recommends their continued integration into science instruction.