TOOL4GENDER aims to prevent gender-based violence by acting at a very early stage (school children between 8 and 16 years old) before their perpetration, through the training of professionals in the field of prevention of gender violence and improvement of their abilities, as well as of the families thanks to the creation of ICT tools. In addition, the children will be able to self-detect sexist behaviours and values thanks to the development of an App. Training Contents will be aimed at developing and ensuring adequate affective maturity for reducing the future likelihood of GBV perpetration and building healthy relationships with others. Key outcomes which will be achieved thanks to TOOL4GENDER will be: increased awareness of how to improve resilience and healthy relationships between school children, the empowerment of girls and greater evidence-based knowledge of the patterns observed before the perpetration of GBV; better training on education and gender approaches and capacity building and formal training that will allow greater knowledge based on evidence of observed patterns (before GBV perpetration) and new opportunities to detect early signs. In addition, a great impact will be achieved in children at schools, through the improvement of their capabilities and abilities to reduce inadequate habits, behaviours, conceptions and prejudices, therefore promoting healthy attitudes in their future relationships, reducing situations of gender violence in youth. As for TEACHERS, PROFESSIONALS OF EDUCATION, SOCIAL WORKERS, and FAMILIES, the training and access to relevant material will allow, thanks to the education in this field in schoolchildren, to diminish gender violence situations by promoting gender equality.