Developing a Supplementary German Vocabulary Workbook for Junior Secondary Students in Kwara State

This study describes the development and preliminary evaluation of a supplementary German vocabulary workbook designed specifically for junior secondary school students in Kwara State, North Central Nigeria. Existing German language teaching materials used at the junior secondary level in Nigeria are predominantly adapted from European-produced resources that lack contextual relevance for Nigerian learners. The absence of locally grounded materials is cited by both teachers and students as a barrier to effective vocabulary acquisition. The study adopts a design-based research methodology, involving an iterative process of material development, expert review, classroom piloting, and revision. The workbook was developed by the researcher in collaboration with three practising German language teachers and draws on vocabulary relevant to everyday Nigerian contexts alongside core vocabulary required by the national curriculum. Pilot testing was conducted with 90 JSS2 students across three Kwara State junior secondary schools over a six-week period. Pre- and post-test vocabulary assessments indicate that students using the supplementary workbook demonstrated significantly greater vocabulary gains than a comparison group using only the standard textbook. Teacher feedback on usability and pedagogical quality was also positive. The study contributes a replicable model for localised supplementary material development. Keywords: vocabulary workbook, German language, junior secondary, Kwara State, instructional material design.