ENGLISH:

This study aimed to discovered if there was a significant difference between the students that used English conversation video on YouTube and the students without used English conversation video on YouTube at SMPN 1 Mendo Barat. The limitations of this study focused on understanding concrete noun and abstract noun. The researcher used quantitative method with quasi experimental design. The researcher had conducted observations with purposive sampling method and multiple choices tests that were given to the students to determine the experimental group used conversation videos on YouTube and the control group which is those that do not used conversation videos on YouTube.

The observation of research showed that class IX C had a lower score than class IX B. Therefore, class IX C as the experimental class and class IX B as the control class with a total sample of 50. The findings of this research showed an increase in students' vocabulary when learning used English conversation videos on YouTube. The test results of the experimental class were pre-test 75,42 and post-test 89,22.
For the control class with the results of the pre-test 56,75 and post-test 79,38, with a total sample of 45 students. With t-obtained 3,111 greater than the ttable 2014. For its 2-tailed significance 0,03 have less score than 0,05. Therefore, it can be concluded that from the statistical analysis, the experimental group was greater performed than the control group. It can be seen that the experimental group mean post-test score was 89,22, while the control group’s post-test mean was 79,38.