Sexuality education is central to overall health, including personal and social wellness and wellbeing, since it requires working not only with the absence of sexual diseases, sexual dysfunctions or infirmities but also with a positive approach to sexuality and interpersonal relationships. Consequently, sexuality education also involves the possibility of experiencing sexual pleasure, intimacy, and safe sexual relationships, contributing to happiness and wellbeing. This multi-dimensional conceptualization of sexuality education implies working with a positive and broader concept of sexual health, encompassing wellbeing and life quality as well as the absence of negative sexual conditions. Therefore, action-oriented projects changing lifestyles or living conditions might contribute to sustainable development, and more specifically to reaching parts of the eight Millennium Development Goals (MDGs).

In this sense, this paper argues that participatory and action-oriented sexuality education in health promoting schools, applying the IVAC approach (investigation, vision, action & change) and using information and communication technology (ICT), plays an important role in fostering the MDGs since it creates conditions for the development of students’ empowerment and action competence. This action competence enables coming citizens to carry out actions that support the MDGs in five different ways.

Firstly, by students acting to promote family planning bycontributing in developing countries to decrease the number of poor household members will allow them to make greater investments in the health and education of children, and better spacing of births to improve childhood nutrition and decreasing poverty (MDG1). Actions in this theme will help to save women's lives by reducing unplanned pregnancies, unsafe abortions and maternal mortality (MDG5); and partially ensuring environmental sustainability since the balance between the use of resources and ecological requirements depend on growth, location, population movements, resource pattern consumption and waste management (MDG7).

 Secondly, by students acting on delaying the sexual activities of adolescents, and the use of contraceptive methods they contribute to reducing child mortality in young mothers, and after closely spaced births (MDG4), and in developing countries they contribute to achieve universal primary education, because premature sexual activity increases the risk of unplanned pregnancy and school dropouts and/or early marriage of girls who stop studying, and increase the number of children in poor families, diminishing their access to education (MDG2).

Thirdly, students could also act to promote gender equality and female empowerment bypromoting sexual health literacy, access to sexual and reproductive health care and environments where girls/women are safe from gender-based violence (MDG3) and in the prevention of HIV and other sexually transmitted infections, as young people are enabled to protect themselves and change social environments making male/female condoms available and supporting the creation of appropriate systems in poor countries to ensure them (MDG6). Finally, students could contribute to a global development partnership, supporting sexual and reproductive health programs by participating in twinning cross-cultural action-oriented sexuality education projects among developing and developed countries (MDG8).

Therefore, this paper intends to present some of the evidence collected in Portuguese researches that support this argumentation.

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