STAD : A SUITABLE TECHNIQUE FOR INCREASING STUDENTS’ VOCABULARY MASTERY

Increasing students’ vocabulary mastery is not an easy way for English teacher in teaching English in the classroom. To realize the difficulties of increasing students’ vocabulary mastery, the English teacher should consider many strategies of teaching. The strategies that are used should be able to make students feel comfortable and enjoy in the classroom and also should be able to encourage and motivate them to learn. One of the strategies is STAD (Student Teams Achievement Divisions). This research focuses on the implementation of STAD to increase students’ vocabulary mastery. The writer would like to find out whether there is a suitable technique or not on students’ vocabulary mastery for junior high school students after applying STAD in teaching and learning process. This research is an experimental study in quantitative research. The research involved two equal qualification of sample groups, they are an experimental group and control group. The instrument that used in this research is vocabulary test. Pre-test were given for both groups, after applying STAD in treatment for experimental group, the pos-test was administered by the two groups, experimental group and control group. The writer found that the mean score of experimental group is 52.59 in pre-test and became 71.66 in post-test and control group is 51.52 in pre-test and became 55.81 in post-test. From the result of mean score from each groups, it can be seen that there is significant improvement from experimental group. Consequently, the use of STAD is more effective to increase vocabulary mastery for junior high school students. And the evidence indicates that teaching English vocabulary by using STAD has significant positive effect and become a suitable technique for increasing students’ vocabulary mastery.


INTRODUCTION
The purpose of English teaching is to improve the students' four skills of listening, writing, reading and speaking with the base of large vocabulary and good grammar.Vocabulary is one of the English components in learning the language because vocabulary is the basic of word for people to speak the language.According to junior high school curriculum, English is the first foreign language which taught as a compulsory subject.Nunan (1991: 117) stated that vocabulary is a list or collection of words to a person both actively and passively.By active vocabulary, it is related to persons' knowledge of words used actively in speaking and writing.By passive vocabulary, it deals with the use in this passive language, that is listening and reading.The basic ability for students in understanding the target language depends on the one's knowledge of vocabulary.The problem will appear if a student does not know English vocabulary very well.To minimize students' problem, the students should have many vocabularies because lack vocabulary often encounter difficulties when speaking English to each other or reading the English texts.
Teaching vocabulary is not an easy matter for English teacher.To realize the difficulties of teaching vocabulary, the English teacher should consider many strategies of teaching.Many strategies can be used in teaching process and the strategies that are used should be able to make students feel comfortable and enjoy in the classroom and also should be able to encourage and motivate them to learn.In teaching and learning English, vocabulary is also as one of English components that should be taught at junior high school.
Many problems appear while the teaching and learning English vocabulary at junior high school they are; students cannot remember the list of words, students were lazy to find STAD: A Suitable Technique for Increasing Students' Vocabulary Mastery J-SHMIC, Vol 4, No 1, Februari 2017 the meaning of word in dictionary, students always use Indonesian language in learning process, students do not care about the material was explained by the teacher, and lack of exercises that are given from the teachers.Beside that the teachers do not use various techniques which make students interest in learning English vocabulary in the classroom, they only focus on the book and explain the material by using traditional teaching.
Actually, the various techniques in teaching English vocabulary are very important in order to motivate students in learning.There are a few techniques can make students active and can improve their emotion, feeling and logical.
One of teaching strategy that has orientation with constructive approaches is learning cooperative by using STAD (Student Teams Achievement Divisions).According to Johnson (1997) the use of learning cooperative especially STAD type has beneficial to motivate students in group so that they can help each other in mastering the material that is given.Beside that the use of STAD also can grow the awareness of students' learning, useful and fun, the students more responsible in learning process, and make students' positive thinking in learning the material that is given.
Student Teams Achievement Divisions (STAD) is the teaching strategy in small heterogeneous group or teams based on the differences of level academic, genders, race, religion, social background and ethnics.STAD was developed by Slavin (1995) and has been used in such diverse subject areas as language arts, social studies, mathematics and science.STAD is also implemented in ESL and EFL areas to develop learners' language skills (Kagan, 1996).In STAD, students are assigned to four member learning teams that are mixed in performance level, gender, and ethnicity.STAD cooperative has 4-6 members in a group.STAD is one of the simple learning cooperative that is created to help the students' socialization.Learning cooperative STAD type is featured by the task structure, purpose and cooperative reward.STAD can influence the feedback between the teacher and the students; there is positive competition between the students.Slavin (1995) states that STAD consist of five major components: class presentation, teams, quizzes, individual improvement scores, and team recognition.The details of each component are discussed as follows: 1. Class presentations This component is mainly constructed by the teacher.Materials are presented and explained to students; however, the students must always realize that they must pay careful attention because the learning content will appear on the worksheet that they will be assigned in the next component.

Teams
Students are divided into groups of four of heterogeneous academic performance, sex, and race or ethnicity.This component is important because it prepares students to do well on the quizzes.All teammates study the worksheet or materials together and need to explain STAD: A Suitable Technique for Increasing Students' Vocabulary Mastery J-SHMIC, Vol 4, No 1, Februari 2017 them to each other carefully.Students must ensure that all members understand the material thoroughly before doing the quiz.

Quizzes
After studying the material or worksheet, students take individual quizzes and they cannot help each other.This component demonstrates individual accountability that each student is responsible for studying the material and working on the worksheet attentively.If every member in the group gets higher scores than previously, this will possibly help the team to improve their scores in the next components.

Individual improvement scores
The idea behind this component is that each student has a performance goal to work harder and better than in the past.All students can improve the team scores if they do better in the quizzes.Students at all levels of achievement: high, average, or low have equal opportunities to work for the team.However, each student has a base score deriving from their score on their last performance.

Team recognition
Team gets a reward if the team's average scores satisfy the criteria.Teacher may have a role in creating how to reward successful group.However, this component does not mainly focus on the award; it rather focuses on the recognition of the students' accomplishment.

Standardization of teaching
English by using STAD in this study as cited by Slavin (2000), the students' ability in each group are chosen heterogeneously.So the ability of one group to the other groups is homogeneous.If it is possible, to make groups the teacher should notice the differences of race, religion, gender, and social background of the students.If in the class the differences of race, religion, gender, and social background of the students are the same relatively.So the teacher makes the group based on the academic ability of each student.Slavin (1984: 75) said that STAD has some components.The first is teams; STAD cooperative has 4-6 students in a group.They are heterogeneous students.They have different level in academic, gender, and ethnic group.Every group has a task to be solved in the classroom.Placement test; the teacher gives the students the test.The question that is given based on the material that will be taught by the teacher.It is to help the students to know the students in understanding the material.
The second is students' creative; to help the students to be active in group work the students is given assignment or responsibility.The third is team study; the teacher makes the team study to work together in a group to solve the material that is given.And ask the students to read the instructions and ask the teacher or their friend about the instruction.And the last is team score and recognition; the teacher gives the score to the students.Slavin (1995: 75)  And then the teacher gives reward to the group, reward is given by the teacher based formula as follow:

Receive Many Kinds of Opinion
In cooperative learning, the students can develop and change their ideas or opinions in a group.For cooperate to handle academic problem and also to passed student structure appreciation to value each other.

Develop Social Skill
In cooperative learning, students can develop their social drill because they always share in a group with their friend and Student study cooperative skill to value other opinion and determine the purpose together.
Gnagey and Ostrowski (1992) said that STAD is a system of cooperative learning which features small heterogeneous teams of 4-6 members who tutor each other on the material in the course and prepare each other for weekly quizzes.Students take quizzes individually but are awarded bonus point on the basis of the team's mean performance.Rather than awarding bonus points to the teams with the highest average quiz scores which worked in favor of teams with more bright, motivated students.
According to Arends (1997) STAD is perhaps the simplest and most straightforward of the cooperative learning approaches.In STAD, the students work in mixedability teams to study the lessons or work on the material presented by the teacher.Then, they work in groups of four until six members before doing individual quizzes.The teams may earn reward based on how much they progress over the previous learning period.The only way that the team can be successful is to ensure that everyone in the group has learned the content and is able to master the quizzes.
STAD or Student Teams Achievement Divisions to give it its full name is a system developed by Slavin (2000).The system offers a way to incorporate individual quizzes into a team context.Team members support each other to learn material presented by the teacher and score points according to individual improvement.And it work procedure: 1. Students are divided into teams.
Four is an ideal number.Teams are chosen heterogeneously.That is to say that a team should consist of a mix of boys and girls and have a spread of ability level.2. The teacher introduces material to be learnt.3. The teacher gives handouts and answer sheets to the teams.Each team should receive fewer sheets than the total needed.For example a team of four would be given two worksheets and two answer sheets.This is to stress the idea of working together.4. Team member practice together.5.The quiz is taken.Students take the quiz individually.If necessary move tables apart to minimize the chance of copying.6.The teacher collects the handout and marks them before the next class.The first quiz becomes the benchmark for team scores.The process is repeated for five or six lessons.7. Once a benchmark is established it is recomputed after every two qizzes: (current benchmark + last quiz + next to last quiz) ÷ 3 8.The teacher keeps track of the improvement point scored.This can be done, individually as a team and for the class as a whole.

The Advantage of STAD
Johnson (1997) the use of learning cooperative especially STAD type has beneficial to motivate students in group so that they can help each other in mastering the material that is given.Beside that the use of STAD also can growing awareness that learning is important, useful and fun, the students more responsible in learning process, and make students positive thinking in learning the material that is given.
Cooperative learning methods like STAD have been proven to be successful among a wide range of subjects and age different levels.Slavin (1995) claims that STAD is the most heavily researched of the entire cooperative learning methods and the positive effects have been consistent in all subjects.The greatest positive effects on students learning occur when groups are recognized or rewarded based on the individual learning of each of the group members.
In teaching and learning process, it is considered the importance of the language classroom.Brown (1994: 173-174) conveys that an integration of these principle and issues yield a numbers of advantages of group work for English language classroom.
The first is cooperative as generates interactive language; it means that group work helps to solve the problem of the classes.That are to large to offer many opportunities to STAD: A Suitable Technique for Increasing Students' Vocabulary Mastery J-SHMIC, Vol 4, No 1, Februari 2017 speak and small group provide opportunities for student initiation for face to face give and take, for practice in negotiation of meeting, for extended conversational, exchanges, and for students adoption or roles that would otherwise be possible.
The second is offers and embracing affective climate; it means that the second important advantage offered by the group work is security of a smaller group of students where each individual is not so starkly on public display to what the student may perceive as critics and rejection.Suddenly, students become increase in students' motivation.
The third is cooperative promotes learner responsibility and autonomy; it means that group work places responsibility for action and progress upon each of the members of group somewhat equally.The fourth is cooperative a step toward individualizing instruction; it means that small group can help the students with varying abilities to accomplish separate goals.The teacher can recognize and capitalize upon other individual differences such as age, cultural heritage, field of study, cognitive style, to name a few by careful selection of small groups and by administering deferent task to deferent groups.
The last is cooperative is genetic term covering a multiplicity of techniques in which two or more students are assigned a task that involves collaboration and selfinitiated language.Note, that what we commonly call pair work is simply cooperative in group of two.It is also important to note that group work is usually implies small group work, that is students in groups of perhaps six or fewer.Large groupings defeat one of the major purposes for doing group work giving students greater opportunities to speak.

Vocabulary
Vocabulary is one of the necessary components in learning language, because vocabulary is the basic word of a language.Houghton Mifflin Company (1992Company ( : 2000) ) added that vocabulary is a list of words and often phrases usually arranged alphabetically and defined or translated; a lexicon or glossary.A person's vocabulary is the set of words they are familiar with in a language.A vocabulary usually grows and evolves with age, and serves as a useful and fundamental tool for communication and acquiring knowledge.
Troike (1995: 216) said that vocabulary knowledge in English as the most important aspect of oral English proficiency.Moreover, Murcia and Rosenweight (1979: 123) describe that the vocabulary is a language that needs continue growth and development for native and nonnative speaker long after grammar and pronunciation are under reasonable control.The quality of students' language skills both receptively and actively depend very much on quality and quantity of their vocabulary.Furthermore, they said that the more vocabulary one has, the more vocabulary he/she will be skillful in the language.
The ability to understand to target language greatly depends on one's knowledge of vocabularyvocabulary in the boarder sense.To understand a text a students must have a good command of the STAD: A Suitable Technique for Increasing Students' Vocabulary Mastery J-SHMIC, Vol 4, No 1, Februari 2017 vocabulary of the target language.Through learning a language does not mean merely learning words.Vocabulary proficiency, however, will enable the students to acquire the skill of listening, speaking, reading and writing (Valette, 1998: 3) In relation to the topic of this research, mastery on vocabulary refers to the students' knowledge of ability to understand something that one has seen, heard, feel and so forth.It is important to master vocabulary because the ability to understand the target language greatly depends on one's knowledge of vocabulary and vocabulary acquisition is an important aspect of speaking (Kimtarsiah, 1998: 3) 1.4 Teaching English Vocabulary by Using STAD Brown (1998: 10) said that the teaching of vocabulary must take into various grading factors.In other words, teacher planners must take careful decisions as to the number of words that learners can or have to master within available time.Moreover, teachers' planning must also be with the grouping of words, in order the new words are presented by presenting new words, a teacher may be able to know the best way to teach vocabulary.Gains and Redman (1986: 264) suggested the following types of vocabularies presentation technique.

a. Visual technique
These pertains the visual memory, which is considered especially helpful with vocabulary retention.Visual techniques lend themselves well to presenting concrete items of vocabulary nouns.Many are also helpful in conveying meaning of verb and adjective.They help students associate presented material in a meaningful way incorporates it into system of language value.

b. Verbal explanation
This pertains to the use of illustrative situation, synonym, opposite, scales, definition, and categories.

c. The use of dictionary
Using a dictionary is another technique of finding out meaning of unfamiliar words and expression.Students can make use variety of dictionaries bilingual or monolingual.
Cooperative learning STAD type is a successful teaching strategy in which small teams.Each with students of different levels of ability, use a variety of learning activities to improve their understanding of a subject.Each member of items is responsible not only for learning what is taught but also for helping teammates learn.Thus create an atmosphere of achievement.Students work through the assignment until all group members successfully understand and complete it (David and Roger, 2001).Brown (1994Brown ( : 1730) ) said that cooperative learning especially STAD type is a generic term covering a multiplicity of techniques in which two or more students are assigned a task that involves collaboration and self-initiated language.David and Roger (2001)  Before learning the new material, the students were given pre test.It was used to find out the initial capability of the class and then the class taught by using STAD for experimental group only.Finally the class got post test to find out the influence of teaching technique which used.
This research was conducted at SMPN 5 Siak Hulu jl.Raya Desa Hangtuah Kabupaten Kampar.The population was the first year students which total number were 128 students.The sample of this research was chosen by using random sampling for all the class (4 classes) and took two classes as sample of experimental and control group, the amount of students to be sample were 32 students.Base on the pre-test scores were concluded that both groups were homogenous.Experimental and control groups had the same characteristics, intelligent and environmental background.
The instrument of this research was vocabulary tests, the test was made by the writer consist of 30 items of multiple choices.The students got pre-test for both experimental and control group, treatment for experimental group only and post test for both experimental and control group at the end of meeting.

FINDINGS AND DISCUSSION
From the presentation and the data analysis, the writer finds out that the total of means of the vocabulary mastery of the experimental group and control group in pre-test, before treatment are 52.59(experimental group) and 51.28 (control group).In significant level 0.05, tobservation is 0.46 and tcritical is 2.00 in degree of freedom (df 62), it means that tobservation less than tcritical.So, the ability level of the two groups for starting points at the beginning of the research was relatively the same.

CONCLUSIONS
The conclusion of this research is divided into two kinds, the first is concerned with the conclusion on theoretical and the seconds are deals with the practical conclusion.

a. Theoretical Conclusion
STAD or Student Teams Achievement Divisions was one of learning cooperative was developed by Slavin (1995) and had been used in such diverse subject areas as language arts, social studies, mathematics and science, STAD is also implemented in ESL and EFL areas to develop learners' language skills (Kagan, 1996).Cooperative learning methods like STAD have been proven to be successful among a wide range of subjects and at different age levels.Slavin (1995) claims that STAD is the most heavily researched of the entire cooperative learning methods and the positive effects have been consistent in all subjects.The greatest positive effects on student learning occur when groups are recognized or rewarded based on the individual learning of each of the group members.
STAD is one of the simplest of all cooperative learning methods.Similarly, Arends (1997) claims that STAD is perhaps the simplest and most straightforward of the cooperative learning approaches.In STAD, students work in mixedability teams to study the lessons or work on the material presented by the teacher.Then, they work in groups of four or five members before doing individual quizzes.Cooperative learning STAD type is most appropriate for teaching well defined objectives, for example, mathematical computations and applications, language usage and mechanics.

b. Practical Conclusion
The use of STAD in teaching English vocabulary was able to make easier and better for the students to acquire new vocabulary understanding.From the finding presented on the previous section showed that the experimental group made improvement 36.26% from the pre-test to post-test.While the control group made improvement 8.33%.The first year students of SMPN 5 Siak Hulu were interested in learning English vocabulary through STAD because they were really involved in the teaching and learning activities, they did not merely sit and listen to the teacher always.In other word, the use of STAD was more effective and it could be applied in teaching English Vocabulary.
The evidence indicated that the experimental teaching by using STAD made the students active in the classroom and could increase the said that to give the score in group work or Februari 2017 cooperative is calculated by calculate the result pre-test and add the result post-test: STAD: A Suitable Technique for IncreasingStudents' Vocabulary Mastery J-SHMIC, Vol 4, No 1,

Table 2 .
Group Reward

Table 3 .
The Mean Score of Experimental and Control Group