Gender stereotypes emerge early.

Bian et al. (open source) find that children at age five do not consider boys and girls different with respect to being 'really, really smart' - the childhood version of adult brilliance. But by age 6, girls are more like to put more boys in the 'really, really smart' category and steer themselves away from games intended for that category.

Common stereotypes associate high-level intellectual ability (brilliance, genius, etc.) with men more than women. These stereotypes discourage women’s pursuit of many prestigious careers; that is, women are underrepresented in fields whose members cherish brilliance (such as physics and philosophy). Here we show that these stereotypes are endorsed by, and influence the interests of, children as young as 6. Specifically, 6-year-old girls are less likely than boys to believe that members of their gender are “really, really smart.” Also at age 6, girls begin to avoid activities said to be for children who are “really, really smart.” These findings suggest that gendered notions of brilliance are acquired early and have an immediate effect on children’s interests.