Currently, the transport sector is a major contributor to global greenhouse gases emissions. The evaluation of projects that promote the decarbonization in cities is mainly focused on calculating the reduction of CO2 emissions. The calculation methodology takes into account the characteristics of the city car fleet where these projects are implemented. In the case of the "SchoolBus" project, promoted by the Braga Municipal Council during the 2018-2019 school year, the average value of reduction was of 34.9 tonCO2eq/year. The number of vehicles circulating in the study area, the emission factor related to the type of vehicle and its fuel and the distance traveled by them were the main parameters used to calculate CO2 emissions. The impacts of the "SchoolBus" project on stakeholders and awareness-raising actions of sustainable mobility can be quantified in terms of CO2, by analyzing the population's interest in joining more sustainable modes of transport. Thus, it is possible to evaluate the potential of the awareness-raising actions, applied in the study area, in the decarbonization in a larger area (i.e. the whole municipality). At the same time, it is possible to compare and analyze the calculated values in relation to the quantified potential range of effects of policy measures on CO2 emissions using transport demand for the year 2030, indicated by the European Commission and adapted to the area of study, by introducing measures of sustainable mobility in the territory.