ABSTRACT

The objectives of this research are: 1) to know whether Quizlet is able to improve the students’ vocabulary mastery or not; and 2) to know how Quizlet is able to improve the students’ vocabulary mastery in reading activity for senior high school students.
This research is a classroom action research taking place in SMA Batik 1 Surakarta. The subject of the research is the students of XI MIPA 3. This research was conducted in two cycles. The procedures of the research were adapted from Kemmis and McTaggart (1988). It consists of planning, action, observation, and reflection. The data were collected quantitatively and qualitatively. The quantitative data were taken from pre-test and post-test, while the qualitative data were taken from field notes, interview, and the students’ learning log.
The results of the research are: 1) teaching vocabulary by using Quizlet can improve the students’ vocabulary mastery in reading. It improves vocabulary aspect that is denotation meaning, verb forms, word synonym, and word antonym. It can be seen through the increase of the students’ test score and the reduction of Google Translate use; and 2) teaching vocabulary by  Quizlet can improve the students’ enthusiasm in learning English. It provides fun learning modes which are liked by the students. Besides, there is error correction in Quizlet, so the students are able to learn vocabulary in a text before reading activity and they became autonomous learners.

Keywords: classroom action research, Quizlet, vocabulary mastery