Latent profile analysis was used to identify different categories of students having different "profiles" using self-reported classroom behaviour. Four categories of students with unique classroom behaviour profiles were identified among secondary school students in Oslo, Norway (n = 1570). Analyses examined how classroom behaviour categories are related to gender and school performance and whether a dual understanding of gender in school is helpful when trying to explain achievement differences as supposed to classroom behaviour categories. Analyses showed that gender was a better predictor of school achievement than classroom behaviour categories, even though the behaviour categories did contribute to the explanation of variance in students' academic marks above and beyond gender.