Gender differences in educational attainment have generated considerable debate. Unfortunately, this debate has been constructed in terms of either the measurement of change in the size of the gender gap over time or attempts to theorise such change. This scholarly divide reflects the commitment of researchers to particular methodological paradigms. Therefore, this paper draws on part of a longitudinal, mixedmethods study conducted in three Sixth Forms in England to examine both the extent and causes of gender differences in attainment. Initially, a questionnaire was completed by 330 students in the Sixth Forms and, subsequently, in-depth interviews, nonparticipant observation and a vignette were used to explore students' educational experiences. The public examination grades students held on entering and leaving the Sixth Form were analysed to establish gender differences in attainment. At the start of students' studies, the size of the gender gap in attainment was found to be relatively modest and this gap narrowed further on completion of the course. The declining relevance of gender to attainment was explicable in terms of students' growing awareness of gender, the convergence of their educational practices and changing patterns of social interaction. Nevertheless, gender became more relevant to attainment the closer issues of occupational inequality were approached.