Abstract
Introduction Culturally responsive language education seeks to connect English as a Foreign Language (EFL) instruction with learners' cultural identities and local knowledge. However, classroom-based quantitative research on the integration of indigenous folklore into primary EFL education remains limited, particularly in Central Asia. This study examined changes in fourth-grade learners' linguistic, speech, and sociocultural competence following the integration of Kazakh indigenous folklore into primary EFL instruction. Methods A quasi-experimental one-group pre-test-post-test design was employed with 100 fourth-grade students aged 9–10 years at a public primary school in Kazakhstan. The 12-week intervention comprised two 45-minute lessons per week and was delivered by the regular classroom teacher. Adapted Kazakh folk narratives, cultural traditions, traditional games, storytelling, role-play, retelling, discussion, and productive language tasks were incorporated into English lessons. Learners' communicative competence was assessed using parallel pre- and post-test forms of a 25-item lexical-grammatical test, three composite speech performance tasks, and a 25-item sociocultural competence test. Paired-samples t-tests were used to examine within-group changes, and Cohen's dz and 95% confidence intervals were calculated. Results Post-test scores were significantly higher than pre-test scores across all three competence domains (all p < .001). Linguistic competence increased from M = 12.84 (SD = 4.63) to M = 17.92 (SD = 4.41), with a mean gain of 5.08 points and a large effect size (dz = 0.84). Speech competence increased from M = 16.27 (SD = 5.18) to M = 22.68 (SD = 4.95), with a mean gain of 6.41 points and a large effect size (dz = 0.98). Sociocultural competence increased from M = 11.96 (SD = 4.88) to M = 18.74 (SD = 4.37), producing the largest mean gain (6.78 points) and effect size (dz = 1.10). All 95% confidence intervals for the mean differences excluded zero. Discussion The findings indicate substantial within-group development in linguistic, speech, and sociocultural competence during the folklore-based instructional period, with the strongest improvement occurring in the sociocultural domain. These results suggest that culturally familiar materials may help learners connect English language use with their existing cultural knowledge and experiences. However, because the study involved a non-randomized one-group design without a control group and was conducted in a single school with one teacher, the observed improvements cannot be attributed exclusively to the intervention. The study contributes classroom-based quantitative evidence from an underrepresented Central Asian context and highlights the potential value of culturally meaningful resources in multilingual primary EFL education.