Thirty high school classes from all over Italy and numerous students and professors belonging to the EEE Project participated in the International Cosmic Day 2021 - the international day dedicated to the physics of cosmic rays - taking part in the webinar that the Enrico Fermi Research Center and INFN they organized on November 10th. The meeting, moderated by Dr. Silvia Pisano, CREF researcher, was articulated through the contributions of Dr. Giuseppe Gallo (Muonic Tomography of Etna) of the University and INFN section of Catania, of Prof. Daniele De Gruttola ( Cosmic ray flow vs. direction) of the University and INFN section of Salerno, and the presentations of the four best analyzes carried out by the schools: the Liceo Scacchi of Bari, the Liceo Galvani of Bologna, the Liceo Righi of Rome and the IIS Staffa of Trinitapoli. International Cosmic Day is an international event born 10 years ago, coordinated by the Deutsches Elektronen-Synchrotron (DESY) of Hamburg, and aims to bring students closer to science by accompanying them in the discovery and study of cosmic rays.