COIL+: integrating experiential and blended learning to advance soft skills and global competence in sustainability education

Purpose This study aims to examine how a STEM-contextualized and Education for Sustainable Development-oriented international co-learning model (COIL+) cultivates soft skills and global competence among agricultural undergraduates in Japan and South Korea – two East Asian countries selected for their shared rural demographic pressures and comparable small-scale agricultural structures. Design/methodology/approach The authors implemented a convergent mixed-methods design across three program iterations (FY2022–FY2024). Anonymous post-program surveys (n = 21 of 51 enrolled; 41.2% response rate) captured self-reported gains in leadership, teamwork, problem-solving, communication and creativity. Three focus groups (n = 9) at four and nine months after program participation explored learning mechanisms and temporal trajectories. Quantitative analyses included descriptive statistics, internal-consistency testing and within-participant non-parametric tests; qualitative data underwent six-step thematic analysis with dual coding. Findings Students reported the strongest perceived growth in teamwork and communication. Thematic analysis pointed to three learning mechanisms: boundary-crossing collaboration, psychological safety supporting leadership enactment, and sustainability-anchored authenticity – operating on different temporal scales. Near-term gains centered on collaboration; longer-arc effects at nine months included transfer of skills to contexts beyond the program. Originality/value This study demonstrates how hybrid, Education for Sustainable Development-based international collaboration can operationalize soft-skill development in agricultural disciplines – a domain rarely examined in the IJSHE literature.