Single-sex school enriches the range of educational opportunities for citizens, enabling the right of parents in their school choice. Sex is one of the factors that influence significantly in predicting the risk of school failure, learning difficulties, motivation for school work and in training election during the post-compulsory stage. This requires the consideration and assessment of educational proposals in terms of gender.

In Spain, single-sex school is presented as a school model called integrated in the so called 'personalized education' organizational option. This pedagogical proposal, initiated by Victor Garcia Hoz, currently has a hundred schools, mostly differentiated by sex. School separation of the sexes of these schools is especially felt in the context of personalized education, which considers the student as the centre of the educational task in its dimension as a person; this implies special consideration of educational practices aimed at educating and promoting freedom of the student, to develop their creativity as a manifestation of their difference, and personal communication between all members of the school community.

Separating the sexes facilitates the aspects described since it eliminates the main element of social pressure that occurs in the classroom; the non-presence of the other sex contributes among other aspects to:

- Social comparison between the sexes is greatly reduced, so that students have more freedom of expression, communication and action.

- Equal opportunities is facilitated: girls and boys feel more detached from social expectations and roles assigned to each sex, and choose their career paths more independently of social stereotypes.

- Teachers have greater ability to create a pro-academic school culture, since students better perceive the difference between the school environment and other environments that often do not value the educational tasks.

As for the personal results of this type of education, research and educational practice is recognized at or above the results of the mixed school, even when taking into account the socio-cultural profile of the families present in both mixed school and single-sex. Not only in academic aspects but also in leadership, socializing with the opposite sex, reducing gender stereotypes, etc.

Other countries around value single-sex school as a school form that is proving effective. To illustrate that, in the United States the number of different public schools has increased exponentially in the last 10 years, fruit of the results perceived by teachers. In the UK and Canada, public and private single-sex schools systematically occupy the top positions in the rankings, despite being significantly outnumbered by mixed schools. In Germany and Australia, governments have promoted programs in this regard.