Intolerance to cultural and individual differences, as well as not respecting human rights and not analysing the information received in a critical way, favours discrimination and exclusion. The aim of this paper is to make a proposal for an intervention to promote tolerance through critical thinking aimed at adolescents aged 14 to 16 years old in the Valencian Community. A review of the basic concepts related to tolerance and the main characteristics of adolescence is carried out, because it is a key stage in such promotion.  The intervention program works on awareness and the acquisition of action tools related to tolerance, intercultural education, education in and for conflict, human rights and the media and new technologies, through the promotion of critical thinking. A participatory methodology that includes intervention at a cognitive, emotional and behavioural level is applied in the program; with a pre-test and post-test evaluation by means of a control and experimental group to assess the results.