Computerized dynamic grammar assessment: A developmental and diagnostic approach to grammar assessment

Grounded in Vygotskian Sociocultural Theory and Dynamic Assessment (DA), this study investigated the effectiveness of Computerized Dynamic Grammar Assessment (CDGA) in improving high school students’ grammar ability, diagnosing learning potential, and exploring students’ perceptions. An explanatory sequential mixed-methods design involved 68 Iranian high school students assigned to either a CDGA or Non-Dynamic Assessment (NDA) group. Independent-samples t-tests showed no pretest difference, whereas the CDGA group significantly outperformed the NDA group at post-test. This difference remained statistically significant after controlling for pretest scores via ANCOVA. CDGA generated learner profiles including actual and mediated scores, Learning Potential Scores (LPS), hint usage, and response times, providing diagnostic insights into developmental readiness and responsiveness to mediation. Thematic analysis revealed positive perceptions of mediation, autonomy, diagnostic feedback, and assessment efficiency, despite limited social interaction and occasional technical challenges. CDGA functioned as both an assessment and learning environment, enhancing grammatical ability while providing actionable diagnostic information for technology-enhanced language assessment and instruction. These findings position computerized dynamic assessment as a practical bridge between rigorous language testing and the broader movement toward formative, data-driven instruction in K-12 education.