Out of the 38 nations studied in the 1999 "Trends in International Mathematics and Science Study" (TIMSS), children in Singapore scored highest in mathematics (National Center for Education Statistics, NCES, 2003). Why do Singapore's children do so well in mathematics? The reasons are undoubtedly complex and involve social aspects. However, the mathematics texts used in Singapore present some interesting, accessible problem- solving methods, which help children solve problems in ways that are sensible and intuitive. Could the texts used in Singapore be a significant factor in children's mathematics achievement? There are some reasons to believe so. In this article, I give reasons for studying the way mathematics is presented in the elementary mathematics texts used in Singapore; show some of the mathematics problems presented in these texts and the simple diagrams that accompany these problems as sense-making aids; and present data from TIMSS indicating that children in Singapore are proficient problem solvers who far outperform U.S. children in problem-solving. (Contains 7 figures.)