In terms of grit in particular, we find impacts on the perseverance elements of grit but not on the element related to consistency of interest, suggesting – consistent with recent literature – that targeting consistency of interest may not be an effective way of cultivating grit among younger students. In fact, we show that the intervention may even crowd out interest – a potentially unintended consequence of the particular behavior our intervention tries to engrain. While this may be a point that is unique to deliberate practice and our intervention more generally, it does point towards the importance of measuring outcomes of social-psychological interventions (or literally all interventions) more broadly to detect potentially negative behavioral spillovers. Finally, and more generally, while our paper contributes to better understanding the potential of cultivating grit among primary school students at scale, further work is still needed to distill what is the most effective combination of socio-emotional skills for the needs of different students.

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