The International Masterclasses "Hands on Particle Physics" is an initiative sponsored by the International Particle Physics Outreach Group and hosted by CERN, Fermilab and multiple research centers around the world. It aims to make particle physics knowledge available to high school-grade students and to create an environment where the students can feel how it is to work on an international collaboration. A central activity during the masterclasses is the rough analysis of real data from particle physics experiments by the students, usually by means of a simple software provided by the experiments. This allows several groups in different countries to carry out the same analysis on similar dates, and then the different groups can be gathered and their results can be compared and combined. The International Masterclasses have been running since the mid-2000s, and the Instituto de Física Corpuscular (IFIC) has participated in most of the editions. This talk will provide a review of our experience and the feedback we have gathered from students and teachers.