This project is partly one of STEM Mentor-Mentee program, which was funded by ACS. The group target is a group of 50 students (mentees) from Sekolah Menengah Kebangsaan Taman Nusajaya, Johor. The scope of this project focuses on educating and exposing the basic concept of environmental sustainability among the secondary school students. The module emphasis on the main elements of environmental sustainability as well as the important of sustainable environment for a better way and survivability of life. The module also incorporated aspects of collaborative culture, critically and creatively think, and foster environmental responsibility for future generations’ sustainability. This module implemented several ways in disseminating knowledge and information. The first activities involved flipped classroom activity where involve videos watching. Second activity requires the students (mentee) to conduct discussion on the poster design and sketching the desired sustainable city. The last activities of this module involve a group presentation. The event was held on 13th of July 2019. For the development and design of Sustainable City, the students were divided into 3-4 persons per group. The students were given a specific time for group discussion n designing the sustainable city. A group of postgraduate students were also involved in this program where they were assigned as the instructor (mentor) to assist the secondary school student (mentee) throughout the program. A set of primary and post questionnaire are given to the mentor and mentee in order to analysed and assessed the outcomes of this project. Both sets of questionnaires were analysed. Based on the results of the questionnaires, it shows better understanding on the concept of sustainable environment have been obtained among the students. Through the conducted activities, the mentees have shown good respond. They are able to obtain new knowledge and enjoy participating in the prepared program.