Critical competence is the most demanded by researchers and the most disadvantaged when it comes to measuring it, according to the results of the project. When it comes to measuring it, according to the results of studies consulted (Livingstone, 2003; Vicent González, 2014; Fedorov et al. 2015; Ferrés, 2018 and 2020; Pereira, 2018). In the studies reviewed on critical competence, a major deficiency was noted in the case of teachers, students, and families when it came to the critical analysis of information published in the media and the use of digital resources. Both the results of scientific studies (Gutiérrez-Marín et al. 2012) and European organizations and UNESCO agree on the need to urgently implement media and critical literacy in virtual classrooms. With the aim of promoting a reflective reading of media messages, this study aims to measure teachers' critical competence through a series of practical exercises based on the analysis of advertising images, news and hoaxes using a quantitative methodology based on a survey, provided online, to teachers in five countries: Spain, Italy, Malta, and the United Kingdom. The surveys yielded valuable data confirming the effectiveness of training teachers through distance and/or face-to-face education in addressing misinformation and media manipulation.