The sample consisted of 272 children enrolled in schools in the urban area of a city situated in the North-East of
Italy: 134 were attending the last primary school class and 138 were attending the first secondary school class; 57%
were male and 43% were female; the prevailing age was, as expected, 10 years for the primary school students, and
11 years for the secondary school students: for this reason the variable school class was adopted instead of the
variable age in the data analyses.