A controlled clinical trial will be performed.~72 participants between 10 and 11 years old will be selected and randomized to participate.~Control group and experimental group will enrolled 36 participants each one. Control group will receive BLS training once. Experimental group will receive BLS training in two consecutive years.~Previous and after training a test will be performed.
A controlled clinical trial will be performed.~School children from the age of 10 to 11 will be selected to learn basic life support (BLS) in a primary school of Zaragoza.~One of the groups will learn BLS in two consecutive years and the other group will learn BLS only the first year.~The investigators think that the knowledge will be better in the group that receives two interventions.