<![CDATA[This study examined the effect of using the Memrise application on students' vocabulary mastery at the tenth grade of SMA Utama Medan. The background of this study was the students’ difficulties in mastering English vocabulary, which often hindered their ability to understand texts, construct sentences, and communicate effectively. Memrise was chosen as the learning medium because it provided an interactive platform combining visuals, audio, and spaced repetition, which made vocabulary learning more engaging and effective. This study applied the experimental quantitative method. The population consisted of all tenth-grade students at SMA Utama Medan in the academic year 2024/2025. The sample included two classes: X-1, the experimental group with 24 students who were taught using the Memrise application, and X-2, the control group with 26 students who were taught through conventional methods. Data were collected through a vocabulary test administered in the form of a pre-test and a post-test to measure the improvement in students’ vocabulary mastery. The results showed that students in the experimental class achieved significantly better outcomes compared to the control class. The mean score of the experimental class increased from 54.95 in the pre-test to 68.08 in the post-test, while the control class only increased from 53.30 to 61.61. Statistical analysis using an independent t-test indicated that the obtained t-value (2.447) exceeded the critical t-table value (2.011) at a 0.05 significance level, it was concluded that the Memrise Application had a significant effect on students’ vocabulary mastery. This suggests that Memrise is an effective tool for improving vocabulary learning among high school students, particularly when integrated into classroom instruction.]]>
