As a case study of the introduction of efficient and effective teaching materials and methods that enhance students' technological literacy in different areas despite the relative lack of classroom hours devoted to technology education in Japanese junior high schools, a front-loaded horn speaker system was proposed as a component of multipurpose teaching materials and methods integrating several areas. Following the development of teaching materials and lesson plans, their effectiveness was evaluated through implementation. Acoustic measurements showed that the horn speaker provided high efficiency in the midrange. Moreover, the results of a post-lesson questionnaire administered to junior high school indicated that the speaker system was highly effective as teaching material. It was therefore concluded that the new design enhanced not only student interest but also their technological literacy, as they demonstrated an understanding of the acoustic mechanism and high satisfaction with their final products.