Wardani, Dewi Kusuma.2024.Developing A Supplementary E-booklet For Students’ Vocabulary Mastery In SMPN 2 Ngadiluwih.. Thesis. Department of English Language Education, Faculty of Tarbiyah, State Islamic Institute (IAIN) of Kediri. Advisor: (I) Bahruddin, S.S., M.Pd.(II) Ria Fakhrurriana, M.Pd. Keywords: Vocabulary, Supplementary Vocabulary Material, Research and Development, Junior High School In learning English, vocabulary is the most basic component because it plays an important role in four skills. Vocabulary learning can be achieved through various media, including electronic books, whether at school or at home. The preliminary study shows students struggle in the classroom with learning vocabulary. Develop e-books and get interested in learning English, particularly vocabulary, for students. This research aims to develop new supplementary vocabulary material to facilitate students learning independently. The research used a method R&D from the branch with five procedures: analyzing, designing, developing, and evaluating. The subject of this research were teacher and seventh grade students in SMPN 2 Ngadiluwih. The instruments of the study were an observation sheet, a questionnaire, and an interview. The preliminary phase of this study is an examination of the needs of the students, which reveals various issues that the students have. The problems are a lack of vocabulary, pronunciation, and grammar structure. From the data, the researcher designs the product, including material, vocabulary, and exercises. After the products final design, it was developed into a real product. The product was developed to be suitable for material for seventh-grade students and curriculum. The product should be validated by the experts to get some comments and suggestions for a better product. After revision, the product was implemented in the seventh grade in SMPN 2 Ngadiluwih. The students tried and gave some comments. The researcher evaluates the student’s comment, and then the last process could use the product. According to the studys results, the product increases students interest in learning English with the e-booklet. The products materials can be realized because of its attractive design. In positive perception, e- booklets are very efficient, flexible, and effective. The students can study independently and have more focus. On the other hand, in a negative perception, e-booklets cannot be opened offline. But even though there are positive and negative views regarding e-booklets, supplementary materials can be used as a way for students to add new learning.

Wardani , Dewi Kusuma .   (2025). Developing A Supplementary E-Booklet For Students’ Vocabulary Mastery In SMPN 2 Ngadiluwih. IAIN Kediri