The members of large High Energy Physics (HEP) collaborations come from all over the world. In the case of the ATLAS Collaboration, many of its members come from Latin American, Middle Eastern and Sub-Saharan countries, and so they understand that in many places it can be a challenge to teach experimental HEP. But all members of the collaboration also recognise the massive potential that the always-increasing university student population has, not only concerning fundamental physics but also regarding computing-sciences skills. For that reason, several outreach teams, which include ATLAS, IPPOG, CEVALE2VE members and many other researchers, have been developing and examining free Open Source technologies to release data and to provide effective web-based and offline environments to run, produce, save and share HEP physics analyses. After several years, and with the help of other outreach programmes like the Virtual Visits, ATLAS established an active community that is not just releasing knowledge, data and resources, but genuinely training new physicists who are pursuing advanced studies in experimental HEP right now.