jats:pThis article investigates the relationship between handedness and abilities in secondary school students, specifically analyzing the effect of handedness on subjective and objective musicality and academic performance. Previous research on the association between handedness and musicality has yielded mixed conclusions. Some studies have documented a positive correlation between musicality and non-right-handedness, but other studies have found no relationship. Here we aim to address some of this uncertainty, using a greater diversity of relevant covariates and a considerably larger sample than previous research. Our dataset of 2,902 participants (age range 10–18) comes from the LongGold project: an international longitudinal study of educational development in secondary school students. Musicality was measured through a self-report questionnaire (Gold-MSI) and perceptual tests; academic ability was determined using a Matrix Reasoning test and school grades. Using regression analyses, our main result is a lack of relationship between musicality and handedness, both for self-reported musicality and objective perceptual ability. In contrast, we found a significant association between right-handedness and higher academic ability. Our results provide a clearer perspective on the nature of handedness and its relationship to abilities, as well as highlighting changing dexterity as an area for future research.</jats:p>