This article uses an added value measure to assess the gender-specific impact of attending a STEM (Science, Technology, Engineering and Math) program. Using the results of the mandatory Colombian national exit exams, we compare the math and reading scores at the end of high school and at the end of college by gender. A difference-in-differences technique combined with propensity score matching is used to address selection bias. We find that the gender-related achievement gap in math and reading scores increases after college affecting women. The gap is larger for those individuals studying a STEM major in comparison with a non-STEM major. Moreover, we find that the gender gap is higher in public and accredited universities.