The project Think Before You Share addresses the alarming gap between what young people know about online risks and how they actually behave. A survey of 46 students at our school revealed that 87% know they should verify information, but only 20% actually do. 65% have never heard of lateral reading — a key source verification technique — and only 26% know tools for recognising AI-generated content. Similar results were confirmed by partner EUTA's survey of 38 young people in the Málaga region, where only 18% verify information before sharing. The project aims to equip 40 young people aged 13–15 from the Czech Republic and Spain with practical tools for critically evaluating online content that they will apply in their daily lives. The main objectives are: (1) developing fact-checking skills — we expect 80% of participants to correctly identify at least 4 out of 5 manipulative messages in the final test and 75% to demonstrate measurable improvement of 30%+ when comparing pre/post tests; (2) increasing digital safety and wellbeing — 85% will create personal action plans with at least 3 specific commitments to change their online behaviour and 70% will actively apply learned strategies 3 months after the project, which we will verify through a follow-up questionnaire; (3) strengthening intercultural competences through Czech-Spanish cooperation, where participants will compare different disinformation contexts in both countries — Czech students primarily encounter anti-EU propaganda while Spanish students face disinformation about migration, and this comparison will show them that manipulation works everywhere, only adapting to the local context; (4) creating and disseminating awareness materials — each of the 8 international teams will create at least 1 campaign output and participants will collectively reach at least 200 peers through peer workshops in both countries. An important cross-cutting objective is to strengthen participants' confidence in communicating in English and in an international environment. The experience of working together in Czech-Spanish teams on real tasks will show them that a language barrier is not an obstacle but a challenge that can be overcome. All 40 participants will receive a Youthpass certificate documenting specific competences acquired during the project. The project contributes to EU Youth Goals #3 (Inclusive Societies), #4 (Information and Constructive Dialogue), #5 (Mental Health) and #8 (Quality Learning) and systematically reflects all horizontal priorities of the Erasmus+ programme: digital transformation, inclusion, environmental sustainability and participation in democratic life.