Every two years, GESM students represent the school at the Southeast Asian Games of German Schools, competing against German schools from across South and Southeast Asia. The event combines high-level athletic competition with opportunities to build international friendships and intercultural understanding. Participating schools come from countries such as Thailand, Malaysia, Singapore, India, Indonesia, Vietnam, and the Philippines. Students gain valuable experience competing in a regional sporting environment while developing teamwork, resilience, and international school spirit.

GESM students regularly compete in interschool tournaments through the Manila International Schools' Athletic Association (MISAA). These competitions provide valuable opportunities to test their skills, represent the school, and experience competitive sport. In addition to MISAA events, students participate in tournaments organized by sports associations and other schools throughout the year, depending on age group, discipline, and available opportunities.

GESM hosts friendly matches and sports tournaments that give students additional opportunities to compete and develop their athletic skills. These events also strengthen connections with partner schools and the wider sporting community. Through on-campus competitions, students build teamwork, confidence, leadership, and sportsmanship in a supportive and engaging environment.

Through its partnership with the Lycée Français de Manille (LFM), GESM students regularly participate in friendly matches and joint sporting events. The collaboration creates unique opportunities for students to compete and connect across cultures. Selected competitions allow athletes from both schools to compete together as the European International School (EIS) team, fostering teamwork, international understanding, and a shared Eurocampus spirit.