The late-1960s implementation of generalized coeducational schooling in France led to a remarkable increase in the success and length of time spent by women in school. Nevertheless, this success remains paradoxical: though more precocious and brighter than boys, girls are relatively absent from the strata of excellence in which a priority is accorded to the teaching of mathematics and physics. This absence is typically explained by the inaptitude of women with respect to the practice of science. This article attempts to show that the social construction of this inaptitude is an effect of male domination and to reveal the social stakes involved in the penetration of male bastions by non-negligible, if still small, number of women.