iESD Cloud is an application dedicated to the promotion of sustainable development through education in virtual space. Users can access this platform via the Internet using their mobile devices and share the latest development and good practices with each other anytime and anywhere. An ESD learning tool through educational game is currently piloted with the aim to promote ‘fun learning’. This game-based learning is instrumental to enhance students’ critical thinking, interpersonal and problem-solving skills. Schools will pick a digital game with reference to their learning needs. Students will compete against each other during the 15-to-20-minute game time in class. Teacher will facilitate post-game discussion and reflection and help students to consolidate their learning experience.