Abstract:
This research had the purpose to discover the effectiveness of Playing the Duolingo level-up game to improve students’ vocabulary mastery. This research was carried out using a mixed method. Students with good English vocabulary competence at seventh-grade junior high school in Ciamis are still low. The average of pre-test value in the experimental group is 61,1 while the minimum criteria of mastery learning (KKM) for seventh-grade junior high school is 67. The sample consisted of two classes with a total number of 37 students taken out of the total population using the random sampling technique. One class as the experimental group was taught using the Duolingo game and the other class as the control group was taught using conventional strategy. The instrument for data collection was pre-test and post-test with 15 numbers of multiple choices tests consisting of 5 items of essays and questionnaires. The data were processed using the mean of the test, the t-test formula, and questionnaires. Data results showed that the t-observed value was higher than the t-table value (>2.000) at a level of significance 0.05 with the degree of freedom (df) 35. Since the t-observed value was higher than the t-table value, it means Ha was accepted and Ho was rejected. Therefore, the finding of the first research question revealed that teaching vocabulary mastery using Duolingo is effective because the score of the experimental group is highest than the one of the control group. It is recommended for English teachers practice Duolingo as teaching media to improve students' vocabulary mastery.
