This article addresses mathematics education in one of the most closed countries in the world, North Korea. It is known that ideology permeates all aspects of life in North Korea, but how exactly do the ideological and substantive mathematical components interact in mathematics education there? What concrete form does this interaction take in actual everyday teaching practice? This article seeks to answer these questions based on interviews with former North Korean mathematics teachers and students who have found a refuge in South Korea. With their help, we attempt to analyze the everyday life of North Korean schools, by reconstructing their concrete features and the routines of North Korean mathematics education. (Contains 3 notes.)