Board games in Japanese classrooms: Data and analysis code

Data and analysis code for: Hitsuwari, J., & Uebo, N. Board games in Japanese classrooms: A waitlist-controlled study of social-emotional skills (manuscript in preparation). This deposit contains: (1) dat_anonymized.csv - anonymized item-level questionnaire data (319 observations from 109 fifth-grade students at two public elementary schools in Osaka Prefecture, Japan; three survey waves; responses are not linkable across waves); (2) analysis_public.R - R script reproducing all analyses and figures reported in the paper; (3) README.md - data dictionary and reproduction instructions. Version history: v2 (2026-09-30) - In analysis_public.R, the Phase 1 difference-in-differences (DiD) estimates (primary, sensitivity, and Tobit analyses) are now coded as the change in the early intervention group minus the change in the waitlist control group (positive = larger increase in the intervention group), consistent with the pooled 2 x 2 analysis. This only reverses the sign of these estimates; the data, models, and conclusions are unchanged. v1 (2026-09-24) - Initial release.