Same-gender role models are likely to improve girls’ math performance. This field experiment examined whether the explanation given for a role model's success also influence children's math performance. Fifth graders were presented with a female or a male role model before a difficult math test and were informed about the cause of his/her math success (effort vs. ability vs. no explanation). The results showed that the gender of a hardworking role model did not influence math performance. In contrast, when the role model's success was not explained or explained by abilities, children performed better with the female role model than with the male role model. The hardworking role model and the female role model allowed reducing stereotype threat among girls.