The present study was aimed to examine the impact of structural and functional style of teaching English grammar on the academic achievement of English language course of male students in second grade of high school in Malayer city in the academic year of 2014-15. According to the goal, the present study was a functional survey and from the perspective of the conduction, it is a quasi-experimental research. The population includes all the high school students in Malayer city in academic year of 2014-15 which were 2600. The sample of the study included 48 students who were selected by cluster random sampling, then, they were divided into two experimental and control groups randomly. Functional method was used to teach experimental group and structural method was applied to teach the control group. In order to gather the needed data, an English teacher- made academic achievement questionnaire was used. To analyze the data, independent t test was used in order to compare the pre-test and post- test scores in each group and to compare the score difference in two control and experimental groups. The findings indicate that there is a significant difference between academic achievements of both groups. The results showed that teaching English grammar functionally is more effective on the academic achievement of high school students than structural method.
