Does playing chess improve the cognitive abilities of children? Can the game of chess help in "educating intelligence"? This document presents the results of six years (from 2005 to 2011) of trials in primary schools of different chess training strategies and a study of the relationship between chess training and improved skills and abilities of children. The trials, sponsored by the Piedmont Regional Committee of the Italian Chess Federation and funded by the Compagnia di San Paolo, were conducted under the scientific coordination of Roberto Trinchero and organisational coordination of Alessandro Dominici. Andrea De Magistris, Mariella Piscopo and Giuliano D'Eredità (University of Palermo) collaborated in the research. Roberto Rivello was in charge of the trial.