THE EFFECTIVENESS OF GROUP INVESTIGATION TO TEACH SPEAKING VIEWED FROM STUDENTS’ SELFCONFIDENCE (An Experimental Study at SMA Muhammadiyah 2 Yogyakarta in the Academic Year of 2014/ 2015)

This research is aimed at finding out whether: (1) group investigation is more effective than direct instruction in teaching speaking at the tenth grade students of SMA Muhammadiyah 2 Yogyakarta in the academic year of 2014/2015; (2) ten grade students having high selfconfidence have better speaking skill than those having low self-confidence; and (3) there is an interaction between teaching method and students’ self-confidence to teach speaking. The researcher employed experimental study in conducting this research. The population of this research was tenth grade students of SMA Muhammadiyah 2 Yogyakarta in the academic year of 2014/2015. The sample consisted of two groups; experimental groups (X MIA 5) consisting of 28 students and control group (X MIA 3) consisting of 28 students. Those two groups were taken by using cluster random sampling. The researcher used self-confidence questionnaire and speaking test as the test instrument of this research. The researcher carried out several steps for collecting data, namely: The first step was giving the questionnaire to the students to measure their self-confidence. The second step was treatment where the teaching method was applied in eight meetings of each class. The third step was post test. The students were given post test using speaking test. The research data were gained using speaking test and self-confidence questionnaire. They were analyzed in the terms of descriptive statistics and inferential statistics including normality and homogeneity. The data was analyzed using ANOVA test (Multifactor Analysis and Variance) and Tukey test. The research findings indicate that: (1) group investigation is more effective than direct instruction to teach speaking in the tenth grade students of SMA Muhammadiyah 2 Yogyakarta in the academic year of 2014/2015; (2) the students having high self-confidence have better speaking skill than those having low self-confidence; and (3) there is an interaction between teaching methods used in this research and the students self-confidence levels in teaching speaking. Regarding to the research findings, it can be concluded that group investigation is effective to teach speaking at the tenth graders of SMA Muhammadiyah 2 Yogyakarta in the academic year of 2014/2015. This result of the research recommends for the teacher to use group investigation method as an alternative teaching methods in teaching speaking skill. It also recommends that the further researcher can use this research as the reference of the research. Keywords : speaking, group investigation, direct instruction, self-confidence, experimental stud