Abstract
In the context of internationalized higher education, academic speaking poses significant challenges, particularly within religious-based institutions where culturally aligned materials are limited. This study evaluates the validity and effectiveness of a Speaking for Academic Purposes textbook developed for Buddhist higher education and embedded with socio-cultural insights. The research adopted a Research and Development approach guided by the ADDIE model. A quasi-experimental post-test-only control group design was employed to examine instructional effectiveness. Fortyeight undergraduate students were purposively assigned to an experimental group [n = 25] and a control group [n = 23]. Expert evaluation of content relevance, instructional design, linguistic accuracy and cultural appropriateness yielded a mean validity score of 3.67 out of 4.00, categorized as very valid. Post-test analysis indicated that the experimental group significantly outperformed the control group in academic speaking performance (df[46] = 4.55, p < 0.001, Cohen’s d = 1.316). Assumption testing confirmed normality and homogeneity of variance. These findings demonstrate that systematically designed, culturally embedded EAP materials can substantially enhance academic speaking competence. The study provides empirical support for culturally responsive curriculum development and underscores the importance of contextually grounded instructional resources in fostering both linguistic proficiency and intercultural competence.
Keywords: Academic Speaking, Buddhist Higher Education, Curriculum Development, Instructional Design, Sociocultural Integration, Textbook Validation.