Earlier quoted context omitted.
Men do better than women at the Math SAT[1]. The male/female ratio is especially high in the higher Math percentiles, where you would expect your best engineers to come from. The polite way to explain this is some kind of "expectations effect", which is possible, but females do dominate at all other aspects of education. We cannot rule out simple innate ability, combined with higher male interest in abstract things.…
Men score better than women on standardized tests in math in some countries, while in other countries women score better ( http://www.econ.ucsb.edu/~kelly/gap_sept09.pdf ). It's almost as if the culture you are surrounded by somehow affects you. In fact the countries with more gender equality that encourage women in the sciences have higher test scores for women!
“If, as the data suggest, young girls display a more developed ‘attitude toward learning’ and teachers (consciously or subconsciously) reward these attitudes by giving girls higher marks than warranted by their test scores, the seeds of a gender gap in educational attainment may be sown at an early age, because teachers‘ grades strongly influence grade-level placement, high-school graduation and college admission prospects.”
http://www.buzzfeed.com/annanorth/why-girls-get-better-grade...