In a setting that prioritises the achievement of Sustainable Development Goals (SDG), sustainable development cannot be achieved without the contribution of female talent. This paper is focused on studying the reasons for the gender gap and the offered strategies to reduce it. The debate on the reasons for the low enrolment rates of girls in technological degrees remains open in the literature. This study investigates the causes of why girls do not choose a computer engineering degree and makes a comparison between ex-ante (secondary school) and ex-post (higher education). Based on a survey of students from both secondary school (229) and higher education (171), a quantitative study on gender differences was performed. The chi-squared test was applied to compute the corresponding p-value. Gender significant differences concerning goals were found (such as, at secondary school, girls preferred to help people, whereas boys preferred to be rich or to have a lot of holidays), and degree preferences (secondary school girls showed great interest in degrees, such as psychology, criminology and medicine, while boys showed great interest in sports sciences and engineering). However, these differences cannot be attributed to the existence of gender stereotypes, to the poor social image of workers in that field, or to the goals to be achieved within this profession. Some proposals are offered to reduce the gap.