LEARNING MATHEMATICS THROUGH ENGLISH IN VIETNAMESE LOWER SECONDARY EDUCATION: COGNITIVE AND LINGUISTIC DEMANDS, EFFORT INVESTMENT, AND PEDAGOGICAL DIRECTIONS

Abstract

 The expanding use of English for subject teaching in Vietnam creates new cognitive and linguistic demands for learning Mathematics at the lower secondary level. This article examines the cognitive, linguistic, and instructional demands involved in learning Mathematics through English, with particular attention to students’ cognitive effort investment. The study employs qualitative document analysis drawing on international scholarship, Vietnamese research, and official policy and regulatory documents. Based on Cognitive Load Theory, the article distinguishes the inherent complexity of mathematical content from additional processing demands arising from language and instructional organisation, while differentiating cognitive effort investment from the broader concept of student engagement. On the basis of the reviewed literature, the article proposes a context-sensitive conceptual model for Vietnamese lower secondary education and identifies pedagogical directions concerning language support, instructional design, learner differentiation, teacher capacity development, and implementation adapted to school conditions.