According to the findings of Programme for International Student Assessment (PISA) 2012 mathematics study, organized by Organization for Economic and Co-operation Development (OECD), the four Chinese-speaking economies (i.e. Chinese Taipei, Hong Kong-China, Macao-China, and Shanghai-China) top the league table of mathematics performance amongst the 65 participating economies (OECD, 2014). In the past decade, attested to the spirits of the new mathematics curriculum standards put forward for the 21st century, the mathematics curricula implemented in these four places called forth building up of students’ higher level of cognitive functioning. PISA 2012 provides a golden opportunity for the educational researchers to examine whether higher degree of cognitive activation in the mathematics lessons (as measured by the COGACT index) is related to higher student mathematics performance (as measured by MATHPVs, a set of five plausible values of the student mathematics proficiency score). In PISA 2012, there are altogether nine cases of cognitive activation to be examined for their frequency of occurrence in everyday mathematics lessons (e.g. The teacher asks us questions that make us reflect on the problem; The teacher gives problems that can be solved in different ways). Because of the classroom environments in the four places are culturally similar but socially different it is of considerable interest in this study to examine whether there are similarities and differences in the classroom practices of cognitive activation in the mathematics lessons (Leung, 2006). The differences, if identified in this study, may shed lights on why the effects of cognitive activation in lessons on student mathematics performances are different across the four Chinese-speaking economies. Drawing data from the PISA 2012, the following two research questions are put forward for examination in this study: 1. Is cognitive activation in mathematics lessons positively related to the student mathematics performance in each of the four Chinese-speaking economies in PISA 2012? 2. Amongst the nine cognitive activations in mathematics lessons examined in PISA 2012, what are the similarities and differences amongst the four high-performing Chinese-speaking economies? Through regression analyses of COGACT on MATHPVs, the finding is that there are statistically significant independent effects (p <.05) of cognitive activations on student mathematics performance for all the four Chinese-speaking economies. Through analyses of variance (ANOVA) of the mean of each of the nine cases of cognitive activations in mathematics lessons across the four Chinese-speaking communities, the finding is that there are a number of cognitive activations the means of which are statistically significantly different amongst the four Chinese-speaking communities. In the light of the findings, recommendations for the betterment of mathematics education in each of the four Chinese-speaking communities are given.