Do young boys and girls understand what leads to academic success (e.g., talent, effort, good teaching, luck) in the same way? Do young girls and boys have equivalent perceptions of their academic competence? Are these beliefs gendered in the same way across sociocultural contexts? In a cross-cultural study of over 3,000 children in grades 2 to 6, ages 7.2 to 13.6, we discovered that boys and girls around the world have very similar ideas about what generally leads to academic success. Moreover, in the few contexts where boys' and girls' academic performances were equal, their beliefs were also equal. However, when girls outperformed boys, their beliefs in their own talent were no greater than boys' beliefs, even though they did have stronger beliefs than boys in other facets of their achievement potential (e.g., putting forth effort, being lucky, getting their teacher's help). Our findings support the generally close correspondance between children's achievement and their competence-related beliefs, with the exception that young girls appear to specifically discount their talent. The effects held regardless of the children's achievement, intelligence, or age (approximately 8 to 13 years). Girls were more biased in some contexts than in others, however, suggesting that competence-related biases are rooted in culture-specific aspects of school settings.