The literature highlights the impact of socio-emotional learning on cognitive skill acquisition (Cunha and Heckman 2007, 2008; Cunha, Heckman and Schennach 2010; Kautz et al. 2014). We want to see if training focused on socio-emotional skills can be a cost-effective solution to boost educational outcomes. We aim to assess which types of delivery of the training can be more cost-effective. We compare different trainings between each other and the control group. We want to learn to which extent supplemental digital education can be used in schools, especially, in case of challenges like COVID-19.