Girls are more likely than boys to use counting strategies rather than higher-level mental strategies to solve arithmetic problems. Prior research suggests that dependence on counting strategies may have negative implications for girls' later math achievement. We investigated the relation between first-grade girls' verbal and spatial skills and the strategies they used to solve arithmetic problems. The present findings are consistent with our hypothesis that individual differences in girls' use of higher-level mental strategies are related to differences in their spatial abilities. Spatial skills positively predicted frequency of use of both higher-level mental strategies (retrieval and decomposition), while verbal skills only contributed to the use of decomposition. Furthermore, the rate of use of the "least" sophisticated counting strategy was "negatively" related to spatial skills. (Contains 3 tables.)