The continuous deterioration of the environment is one of the major concerns that societies are facing nowadays. As a response to this challenging situation, the general assembly of the United Nations (UN) created the 2030 Agenda, proposing 17 Sustainable Development Goals (SDGs) to foster sustainable development. Thus, the significance of educating in values related to sustainability and care for the environment must acquire a relevant importance in the education system to provide an Education for Sustainable Development (ESD) in Science, Technology, Engineering and Mathematics (STEM). Therefore, it is necessary to incorporate teaching methodologies that are able to connect with students and to generate enriching experiences. In this regard, it can promote knowledge of the environment and provide a service to the community to ensure sustainable development. This research presents the design, implementation and evaluation of a Service Learning (SL) methodology as an ESD strategy in a university course. Precisely, it describes the development and evaluation of an SL project implemented in a general science subject during a 2020/2021 course taught at the Teacher Training College of the University of Extremadura (Spain). A total of 46 students participated in the study on a voluntary basis. A pre- and post-test methodology was used to assess the suitability of SL as an ESD strategy, resulting in a significant increase in the students’ knowledge about the innovative teaching strategies to work with suitable contents after the project, as well as in their knowledge about SDGs. Moreover, the students’ participation in the SL project made them aware of the community implications in maintaining the environment and generating benefit for the whole community. In addition, this research shows how the SL teaching methodology is an important tool for the achievement of both curricular competences and environmental awareness, since theoretical knowledge is applied to tangible work to perform a real community service, and therefore is a very suitable teaching strategy to be applied in EDS.