Shiraz University Teaching English as a Second Language Quarterly 2981-1546 45 4 2026 09 01 Evaluating a Classroom-Based Grit Intervention for L2 Grit and English Proficiency among Iranian EFL Learners 133 151 8901 10.22099/tesl.2026.56109.3506 EN Akram Alaedini Department of English, Isf.C., Islamic Azad University, Isfahan, Iran Azizeh Chalak Department of English, Isf.C., Islamic Azad University, Isfahan, Iran Ahmad Reza Lotfi Department of English, Isf.C., Islamic Azad University, Isfahan, Iran Journal Article 2026 05 14 Despite growing attention to the role of grit in second language learning, empirical evidence on the effectiveness of interventions to increase grit remains limited. A recently identified personality trait known as 'grit' could forecast individual success across various professional and academic fields. This study investigated whether grit, as a noncognitive trait, can be developed through a classroom-based intervention. In a quasi-experimental study, 42 Iranian EFL learners were conveniently selected and randomly assigned to an experimental group (a classroom-based grit intervention designed to foster perseverance and sustained effort) or a control group (standard instruction). The data were collected using the L2-Grit Scale and final exam scores. The grit intervention was implemented over approximately two months across 16 sessions with a two-month follow-up period. A two-way mixed ANOVA with repeated measures indicated that the grit intervention significantly improved learners' grit and English proficiency (p<0.01), and that improvements were maintained at follow-up (p<0.01). The findings may benefit EFL teachers, learners, and curriculum developers, considering the importance of grit on achievement. In the future, classroom-based instruction incorporating grit-oriented activities might be planned to enhance learning by fostering learners' positive attributes. https://tesl.shirazu.ac.ir/article_8901_4b1a7eaf888797e5971322194978dab8.pdf