TESMUN is an academic simulation of the United Nations where students play the roles of delegates from different countries as well as the people from the House of Representatives of Nepal. They attempt to resolve real-world problems with the policies and perspectives of their assigned countries and assume the roles of the Nepali political leaders. This TESMUN is a grand session of students where they research, inquire and debate. Like many universities, high schools, and non-profit organizations, The Excelsior School has also been organizing the Model United Nations' sessions to empower the students with the necessary skills for the 21st century.

It is a platform where students face their fear of public speaking, develop negotiation skills and construct the relations among human beings as a dimension of communication.

On top of knowing facts of the contemporary world, through their participation in the MUN sessions, they equip themselves with skills of handling various activities of day-to-day life as a scholar, an activist, or a visionary leader.

As The Excelsior School wants to develop informed, creative, and responsible citizens for the country and the world, the school has been organizing MUN sessions and may the 9th TES-MUN session be instrumental to realize its objectives.