Mu Alpha Theta, the national high school and two-year college math honor society inducted. Mu Alpha Theta has more than 100,000 members from over 2,420 chapters in the US and 23 foreign countries. Each member meets the rigorous requirements for membership. The principal purpose of Mu Alpha Theta is to stimulate a deeper interest in mathematics. Members participate in competitions, organize math-related activities and be of service in a math-related manner.