The Effectiveness of Using The Goat’s Secret; Illustrated English Short Stories to Improve Grammar Ability of The Second Grade of SMPN 20 Purworejo in The Academic Year of 2015/2016

This study is aimed to describe whether or not there is any the effectiveness of using The Goat’s Secret; illustrated English short stories to improve grammar ability of the second grade of SMPN 20 Purworejo n the academic year of 2015/2016.  In order to master English  well, the elements of the language such as vocabulary, grammar, and sound system must also be taught to the  students  as  the  basic  knowledge  to  words  the  English  use  and  skill.  Through  the  study  of grammar, students would become more familiar with the grammar of their native language and that this familiarity would help them understand, so they can speak and write better. The result of the  research  revealed  that  the  mean  score  of  control  group  is  76.27  fell  in  good  category.  The mean score of experimental group is 81.93 fell in excellent category.  Besides, to know whether Ha is accepted or rejected the researcher consulted to the t-test. The t-value was consulted to the t-table  at  the  5%  significance  level.  It  shows  that  t  table  is  2.000  and  the  t  value  is  14.275.  It means that t value is higher than t table. Therefore, it can be concluded that the use of illustrated English  short  stories  in  improving  students’  grammar  ability  at  the  second  grade  students  of SMPN 20 Purworejo in the academic year of 2015/2016 is effective.