International comparative studies and cross-cultural studies of mathematics achievement indicate that Chinese students (whether living in or outside China) consistently outperform their Western counterparts. This study shows that the gap between Chinese-Australian and other Australian students is best explained by differences in motivation to achieve, attributing success to effort, the influence of parental help and the use of extra mathematics curricula. The argument explored is, in order to promote students' mathematics achievement, we must improve the pedagogical knowledge of classroom teachers of mathematics, as well as to encourage parents' involvement in the mathematics education of their children and to promote students' motivation to learn mathematics.