Validating an Environmental Character Education Model for Upper-Secondary Students on a Telegram-Based Learning Platform: A Mixed-Methods Study

This mixed-methods study validated an environmental character education model for upper-secondary students and examined short-term score change after a Telegram-based learning programme. The qualitative phase used thematic analysis of environmental education, character education, and environmental ethics texts, followed by three Delphi rounds with 20 experts. The resulting 11-component framework informed a 76-item questionnaire administered to 384 upper-secondary students in northwestern Iran selected through multistage cluster random sampling. Factor analyses supported the 11-component structure (Kaiser–Meyer–Olkin Measure of Sampling Adequacy (KMO) = 0.850; explained variance = 61.89%; root mean square error of approximation = 0.056), although patience and tolerance showed a weak higher-order loading. A one-month Telegram-based programme was then implemented using component-aligned persuasive statements, short stories, animations, films, music, and environmental prompts. Mean scores increased from pretest ( M = 3.83, SD = 1.17) to posttest ( M = 3.92, SD = 1.19), t (383) = 8.86, p < 0.001, dz = 0.45. The raw change was small and is interpreted cautiously as short-term score responsiveness rather than causal proof of character development.