%A SRI LESTARI 1013135007 %J Digital Library %T IMPROVING STUDENTS VOCABULARY MASTERY BY USING ROSSWORD PUZZLE GAME AT THE FIRST GRADE OF SMA PGRI 1 BATANGHARI %X The existence of vocabulary is considered important since it should be acquired to express or share ideas to other people effectively. Crossword puzzle game is regarded as one of the effective game in learning vocabulary. Nation (1074:253) states that puzzles are teaching techniques, which bring the learners' motivation. It combines teaching students' definitions by giving the students experience in writing the words they are learning, which is an effective part memorizing vocabulary. From the researcher is experience of English teacher at SMA PGRI 1 Batanghari, it was revealed that the students could not do reading exercises well because they had lack of vocabulary. Most of them got difficulties in understanding the content of the text. They spent a long time to consult the dictionary to get the meaning of most of the words in the text. It is such a waste of time so that the students cannot answer all of the questions. It also happened that most of the students were reluctant to speak because of their limited number of vocabularies. They often felt frustrated when they were asked to tell or express something. In line with the problems above, the researcher conducted a classroom action research at the first grade of SMA PGRI 1 Batanghari. The subject of? this research was class X which consisted of 35 students. The teacher was the researcher. The objectives of this classroom action research are to find out whether crossword puzzle game is able to improve the students' vocabulary mastery especially in noun, verb and adjective to improve the quality of the teacher's teaching performance and to improve the students' participation during the teaching learning process while crossword puzzle game is implemented. This research was conducted in two cycles. Each cycle consisted of planning, action, observation, and reflection. The researcher used indicators dealing with the learning product which covered the students' participation during the teaching learning process and the teacher's teaching performance. To collect the data of the 3 learning product, the writer used vocabulary test as the instrument and to collect the data of the learning process, the writer used observation checklist. The indicators showed that 70% of the students had to gain score 66 or more, the teacher had to reach score 80 in the teacher?s teaching performance and 80% of the students had to be actively involved 90% of the teaching learning process. Students' vocabulary scores at cycle I showed that only 21 students (60%) could get score > 66. Meanwhile, after cycle 2 had been conducted, there were 28 students (80%) who passed the KKM (Kriteria Ketuntasan Minimal). For the learning process, that was, the students' participation during the teaching learning process, at cycle I, there were 23 students (66%) who followed -80`% of the teaching learning process and 32 students (91%) who followed >80% at cycle 2. Meanwhile, for the teacher's teaching performance, the teacher achieved score 65 at cycle I, and achived score 81 at cycle 2. Referring to the result of the research above, it can be concluded that crossword puzzle game was successful in improving the students' vocabulary mastery, the students' participation during the teaching learning, process and teacher's teaching performance at the first grade of SMA PGRI 1 Batanghari. %L eprints18706