This study was conducted from the perspective that the under-representation of women in science is, at least partially, a consequence of learning, and therefore, may be considered a symptom of a hidden curriculum in science education. A nine page review of the literature is presented on this subject. This study investigated the direct and indirect influences of sex and several intervening variables on the quantitative science course selection among college undergraduates using the High School and Beyond database. The analyses yielded three major findings: (1) after statistically controlling for all of the other independent variables in the model, being female still resulted in taking fewer undergraduate quantitative science courses, (2) the number of high school science and math courses was the most important mediating variable between SEX and QUANTITATIVE, and (3) within-sex analyses indicated strong interactions between sex and several of the other independent variables. Contains 50 references. (PR)