Our world is undergoing a series of changes that are taking it to an unsustainable situation. In addition to alerting the population, we must seek education towards a more sustainable world. This research proposes the realization in Alcoy (Spain) of some urban itineraries with mobile devices and with secondary school students, in order to promote an improvement in awareness and action on environmental problems. This activity aims, among other objectives, through informal learning and outside the classroom, to raise awareness among secondary school students about the environmental problems that threaten us. With the completion of a questionnaire, after carrying out these urban itineraries, the results of 214 students confirm that, with this type of activity, there is a notable improvement in the level of awareness and concern for environmental problems. It is also detected that men prefer these types of environmental awareness tests, compared to women, who prefer tests that have a more creative and artistic theme. It is worth continuing to propose this type of activity among students and improve their approach by forecasting, planning, and improving the training of the teachers involved in it.