Linguistic Identity, Drive, and Scholastic Performance: An Investigation into the Cognitive-Affective Determinants of Second-Language Acquisition among Yoruba-Speaking Learners

The relationship between how learners see themselves as speakers of their mother tongue and how well they go on to acquire a second language remains one of the more contested questions in applied linguistics. This paper takes up that question in the specific context of Yorùbá-speaking learners of English in southwestern Nigeria, a population whose bilingual experience has rarely been theorised on its own terms rather than borrowed wholesale from Western second-language acquisition (SLA) literature. Rather than reporting new empirical data, the paper builds a conceptual argument: it draws together three strands of theory — sociolinguistic identity, motivational psychology, and models of academic achievement — and proposes an integrated framework for understanding why some Yorùbá-speaking students thrive at English while others, despite comparable schooling, do not. The paper argues that linguistic identity and motivation do not operate on parallel tracks but interact, with a learner's sense of ethnolinguistic belonging shaping the kind of motivation that becomes available to them, which in turn shapes classroom engagement and, ultimately, measurable achievement. A testable model is proposed, together with a methodological blueprint — instruments, sampling logic, and analytic strategy — for the empirical study that would be required to validate it. The paper closes by considering what such a study would mean for language-in-education policy in Nigeria, where English remains the official medium of instruction despite competing, often unresolved, loyalties to indigenous languages.