This study revisits the seminal question of the effectiveness of education for sustainable development (ESD) by adopting a novel approach. Little is known about the effects of ESD as a teaching approach to develop students' action competence for sustainability. This study therefore adopts a three-wave longitudinal design, tapping into the development of 760 Swedish upper secondary students' action competence for sustainability related to their experience of ESD teaching. We can conclude that ESD has an effect on the students' action competence for sustainability. Our results show that it is possible to promote students' action competence through ESD, but our findings also reveal that such a development process takes time and thus the contribution of longitudinal research is important.