Xu, W. and Chang, H. 2026. A Study on Classroom Engagement in Gamified English Instruction in Elementary Schools Across Different Class Sizes: A Case of a Summer Volunteer Teaching Classroom in Longyou County, Zhejiang Province. Journal of Educational Theory and Practice. 3, 4 (Oct. 2026). DOI:https://doi.org/10.62177/jetp.v3i4.1768.