The Effect of Using Scrabble Mobile Phone Games to Develop Students' Vocabulary Knowledge

The purpose of this research was to obtain empirical evidence on the effect of using scrabble mobile phone games to develop students' vocabulary knowledge. In this research, a quantitative method was chosen, and it was modified into a quasi-experimental study with multiple choices as the instrument of this research. Students from the seventh grade of a junior high school in Jakarta were chosen through purposive sampling as the sample from the research population. 60 students were divided into two classes. 30 students from VII A were selected as the controlled class, and 30 students from VII C were selected as the experimental class. The data were collected from the result of the pre-test and post-test of both classes. According to Setyawarno, the data was analyzed using a normality-test then proceeded with a homogeneity-test to conduct a T-test. The study found a difference in the mean score of the two classes from the post-test result, in which the experimental class got a higher score than the controlled class. The post-test result of the experimental class was 77.67, while the post-test result of the controlled class was 80.93. Moreover, the study found that the T-observation was 13.509, and the T-table with df 58 insignificant level degree of freedom 5% was 1.67. The data result proved that T-observation is higher than T-table., indicating that the null hypothesis (H0) was rejected and alternative hypothesis (Ha) was accepted. Thus, it proved that using scrabble mobile phone games was effective at a moderate level to develop students' vocabulary knowledge.