This dissertation contributes to our understanding of the ‘class’ and gender dimensions of educational inequality. In doing this, it uses a “structure-disposition-practice” model that is rooted in Bourdieu’s theory of cultural and social reproduction but also draws from the theoretical formulations of subsequent sociologists to elaborate on the core concept, habitus, and make it more amenable to quantitative analyses. Habitus is a socialized set of dispositions that shapes how individuals orient to the social world, including their perception of their life chances and corresponding styles of thought and behaviour. The model posits that students’ habitus is a formative influence on how they react to their educational environments and affects their academic achievement. Furthermore, students’ habitus is affected by both their social ‘class’ and their gender, and these ‘class’ and gender differences help explain ‘class’ and gender disparities in educational achievement. Working with multilevel Canadian data from the linked PISA-YITS surveys, this study uses structural modeling to examine the relationships between family socioeconomic status, sex, habitus, academic practices, and academic achievement. As well, school contextual effects are included. A number of the findings were consistent with hypotheses. Most notably, the results provide some evidence that students’ family SES significantly affects their habitus and that their habitus significantly affects their academic achievement. For the most part gender differences in the model were modest, but a few differences were evident: the boys outscore the girls in math and science while the girls excel in reading, students’ SES has a relatively stronger effect on the girls’ academic achievement than on the boys’ achievement, while students’ habitus affects the boys’ academic achievement more strongly than the girls’ achievement. Finally, the average SES of the schools students attend affects both the boys’ and the girls’ academic achievement, but this effect is stronger for the boys, and the effect of the boys’ habitus on their academic achievement diminishes slightly as the average SES of the schools they attend increases; no such contextual interaction was evident for the girls. Overall, the results of this study give qualified support to Bourdieu’s framework and the potential of habitus and the “structure-disposition-practice” model to help us understand ‘class’ and gender differences in academic achievement.