This study addresses the urgent need for innovative solutions to environmental issues by focusing on youth development within educational institutions, which play a crucial role in fostering environmentally conscious behaviors. Despite increasing awareness, there is a gap in understanding how educational settings can effectively promote sustainability through collaborative approaches, such as co-creation as an open innovation model and user engagement strategies. This research investigates the mediating role of co-creation between environmental knowledge and environmental performance, comparing university and vocational students. Data were collected from 678 respondents in Thailand and analyzed using structural equation modeling and multigroup analysis. The findings reveal that environmental knowledge positively influences environmental performance and co-creation activities for both groups, with a more significant mediating effect of co-creation among vocational students. This suggests that vocational students respond more effectively to practical, collaborative approaches to digital innovation in the environmental context. The study also highlights the relevance of the Information Deficit Model, which posits that individuals often do not engage in sustainable behaviors due to insufficient knowledge or information. These results demonstrate the critical role of educational institutions in enhancing sustainability practices by leveraging co-creation and environmental knowledge. The insights from this study are valuable for educators and policymakers seeking to develop user engagement strategies tailored to different student groups, ultimately improving environmental performance and fostering innovation in sustainability practices.