The INFN Outreach Cosmic Ray Activities (OCRA) project involves 24 divisions of the Institute all over Italy and offers activities for both students and teachers. The International Cosmic Day - ICD, organized by DESY, is one of the OCRA activities common to all local groups and consists in inviting high school students to carry out hands-on measurements of the cosmic ray flux and to learn about the related physics background.
This paper describes in detail the latest edition of the OCRA ICD, which was organized both in presence at the different sites and online, focusing on the educational value of both modes, also through the use of a questionnaire administered to the participating students at the end of the day's activities.