DEVELOPING A SUPPLEMENTARY OF ENGLISH VOCABULARY MATERIAL BY USING CONTEXTUAL TEACHING AND LEARNING METHOD AT VIII GRADE OF SMP MAMBA'USSA'ADAH PANDANHARUM GROBOGAN

Keywords: development, supplementary vocabulary mastery, contextual teaching, and learning (CTL) method.

The aim of this research is to develop a product in the form of an additional book entitled "the complete vocabulary building" using the contextual teaching and learning (CTL) method, namely a method that links material to everyday life, so that learners can easily improve vocabulary. said the 25 class VIII learners at Mamba'ussa'adah Middle School, Pandanharum, Grobogan

Research and development are one of the research methods used by researchers in this research. In this research, the researcher developed a product in the form of an additional book of English vocabulary mastery. Researchers used six Tomlison development procedures in this research, namely: 1. Need analysis, material development, expert validation, tryout, revision, and final product.

The results of this study show that there is a significant increase in the vocabulary of class VIII Mamba'ussa'adah Middle School learners. This is confirmed by the results of the needs analysis which states that learners have very minimal vocabulary in English, whereas after conducting a try out material evaluation the results state that there is an increase in learners' vocabulary after the development of an additional book entitled "the complete vocabulary building”. It was concluded that these results could be concluded that the development of additional books on English vocabulary mastery entitled "the complete vocabulary building" brought significant improvements.