Abstract There is growing evidence that immersive learning can enhance motivation and engagement. However, research that explores how motivational states are transformed into engagement, especially within the context of Augmented Reality (AR) is rather underdeveloped. The current study aims at predicting and explaining student engagement in terms of the four motivational dimensions of the ARCS, namely attention, relevance, confidence and satisfaction. The study used an explanatory mixed methods design comprising an online survey followed by semi-structured interviews. 106 pupils from four Scottish primary schools participated in a series of AR-supported learning activities embedded in the classroom curriculum. Partial Least-Squares analysis explained approximately 55% of the variance in pupil engagement in terms of their motivational levels of attention, relevance, and satisfaction, demonstrating a moderate-to-strong predictive capability. The followed-up qualitative analysis of the structured interviews provided a more in-depth analysis of how ARCS motivational dimensions influence pupils’ engagement. Study findings can help researchers to better understand the dynamics linking motivation and engagement. It can also help practitioners in designing more engaging and impactful AR-supported learning activities, targeting young learners.