The PREVIENE Project uses a quasi-experimental approach with a convenience sample size of 300 children (grade 3, 8-9 years old) from six primary schools in Granada (Spain) (2 classes per school x 6 schools = 12classesin total). With the average class size of 25 children and the expected recruitment rate is 90%, two classes will be selected in each participating school. All 79 primary schools in Granada will be invited to participate in this study. The schools will initially be contacted by email followed by a phone call. Research team will arrange a meeting with the interested schools and their staff (principal, physical education teacher and other relevant teachers). At this meeting, the researchers will explain the main objective of this study and the inclusion criteria for schools' participation: 1) At least 2 classes of grade 3 children at school, 2) the average class size has to be 25 or more children. Once determined the schools that satisfy the inclusion criteria and express their willingness to participate, a total of six schools will be randomly selected.