The background of this research is related to the lack of students’mastery of the grammatical pattern, especially simple past tense at the Eighth grade of MTs. Manabi’ul Falah. In addition, the English teacher hardly ever used the innovative teaching method to teach English to students. The objective of this research was to know the improvement of students’ mastery of simple past tense after being taught using Numbered Heads Together.
To achieve the research objective, the writer conducted classroom action research. The subject of this research was the students at the Eighth grade of MTs. Manabi’ul Falah Pati in the academic year of 2015/2016. The total number of students was 16 male students. In conducting the research, the writer used two cyles,in each cycle there were four steps, they were planning, acting, observing and reflecting. The writer used test and observation as the techniques to collect the data.
The finding of this research showed that the use of Numbered Heads Together to improve students’ mastery on simple past tense was successful. It can be seen from the students’ average score in pre cycle was 51,25, while it was 64,67 in cycle I and it was 75 in cycle II. In one hand, it was improved about 43,5%.