*3.2. Sample*

It was not possible to randomise the selection of participants due to the small starting population size, and also because participation required voluntary consent.

The study had a sample of 158 students, between 8 and 15 years of age, 79 (50%) of whom were girls, and with an average age of 12.17 years (Std. Deviation = 1.79). The participants came from di fferent countries, although the majority were from Morocco, Honduras, Gambia, India and the Dominican Republic. Sixty-two percent were first generation immigrants and 38% second generation. Among them, 17.7% arrived in Spain the same year that they began their participation in the programme (2018), 19.6% arrived in 2017, 11.4% between 2014 and 2016, and 13.3% over five years ago (between 2007 and 2013). Moreover, 48.7% of the participants were under 12 years of age; and 51.3% were between 12 and 15. At the time of this study, 51.3% of the minors lived in a nuclear household with their parents; 12% in a household with more than two nuclear families (with extended family); 19.6% in a single-parent family; 3.8% with grandparents or other relatives; and 12.7% in a single-parent household but with other relatives. Participants' characteristics are depicted in Table 1.



Source: the authors.

The programme began at the start of the 2018–2019 school year, and the outcomes of the participants were observed during that year. Before the evaluation, the informed consents were given for each father/mother and/or legal guardian, and only after obtaining the corresponding permission were the tests administered.
