This article aims to measure the gender gap in mathematics based on standardized tests in Colombia, which are presented at the end of high school and higher education. Data from the Instituto Colombiano para la Evaluacion de la Educacion (ICFES) corresponds to the results of the Saber 11 and Saber Pro tests. Based on a fixed effects model, it was found that higher education contributes significantly to the reduction of the gap in math and that this reduction is greater among students who chose careers in Science, Technology, Engineering and Mathematics (STEM) than those students who did not (not STEM). These results can serve as input for decision making on educational policy, and even on labor policy.