This study revisits the seminal question of the effectiveness of education for sustainable development (ESD) by using a novel longitudinal approach. Scholarly attention in the past decade has been increasingly directed towards the concept of action competence for sustainability. However, little is still known about the effects of ESD as a teaching approach to help 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' self-perceived action competence for sustainability as related to their experience of ESD teaching at their school. We can conclude that ESD has effect on students' action competence for sustainability. Our longitudinal growth models show that it is possible to develop students' action competence, which is affected by their experience of ESD teaching at their school. However, the students did not significantly develop the action competence component confidence under their own influence. Our findings reveal that developing students' action competence by implementing ESD in formal education takes time, and they shed light on the need for longitudinal research studies in the field of ESD.