The Effect of Using Brainstorming Method on Eighth Grade Students’ Vocabulary Mastery at SMP Muhammadiyah 2 Kalisat in 2018/2019 Academic Year

Vocabulary is one of the major components of a language which have to be master by learners. Because, without having adequate vocabulary mastery, learners will unable to understand the structure and function of the language.
One of the teaching method to study vocabulary is brainstorming. Brainstorming is popular method that was developed by Alex Oxborn in 1950. Brainstorming method is a quick and easy way to generate ideas for problem solving and innovation in a new way, craeative, logic, originality and spontaneity.
The aim of the research to find out The effect of Brainstorming method to increase students’ vocabulary mastery. It tries to reveal whether there is any significant effect between those who are taught with Brainstorming method and those who are taught with Lecture method.
This research design used quasi-experimental research. The subject of of this research were 18 students of eighth grade students at SMP Muhammadiyah 2 Kalisat in the academic year 2018/2019 where 9 students of VIIIA and 9 students of VIIIB. VIIIB was chosen as the experimental group which was taught using Brainstorming method as the treatment while VIIIA was chosen as the control group which taught using Lecture Method.
The result of this reseach shows that there is a significant different in the students’ vocabulary mastery who are taught by using Brainstorming method and those who are taught with Lecture Method. The significance of Mann Whitney U-Test was 0.011 < 0.05 level of significance. It means that using brainstrorming method has significant effect on the students’ vocabulary mastery.
Key Words : Brainstorming Method, Vocabulary Mastery