This study investigates the developmental trajectory of subject-verb agreement comprehension in typically developing Hindi-speaking children across Grades 1 to 5. Given Hindi’s morphologically rich verb agreement system, which encodes person, number, and gender, the study aimed to examine how children acquire sensitivity to these grammatical features with age and educational progression. Using a cross-sectional design, seventy-five monolingual children from semi-urban government schools participated in an auditory grammaticality judgment task consisting of fifteen sentences—five grammatically correct and ten with systematic agreement violations. Each child’s accuracy was recorded to assess morphosyntactic proficiency. Results revealed a steady increase in performance, with mean scores rising from 8.0 in Grade 1 to 13.16 in Grade 5. Statistical analysis using the Kruskal-Wallis Test (χ² = 2.13, p < 0.05) and Mann-Whitney U Test (Z = 1.96–2.84, p < 0.05) confirmed significant differences across grades, indicating a strong correlation between age, academic level, and agreement mastery. Younger children, particularly in Grades 1 and 2, exhibited difficulties with gender agreement, reflecting higher processing demands in morphologically complex constructions. The findings underscore that grammatical agreement competence in Hindi develops progressively through cognitive maturation, increased linguistic exposure, and structured grammar instruction. The study contributes to understanding Hindi morphosyntax acquisition and informs pedagogical and clinical practices for supporting language development in semi-urban populations.