Abstract The overarching goal of this study is to investigate whether teachers of Swedish at upper secondary schools in Sweden feel that they know how to teach critical literacy, especially on the Internet, and also if they know how it is taught. It also investigates the difficulties teachers experience in teaching critical literacy. A secondary goal is to investigate the knowledge of critical literacy among students at upper secondary schools in Sweden. The study is based on quantitative and qualitative research. The research consists of two parts. The first one is made through a digital survey-machine. The answers can be analyzed in both a quantitative and a qualitative way. The selected group for the survey consists of both students and teachers. The second one is based on interviews with three teachers. The majority of earlier research in this field focuses on the information seeking process. Not much has been written about critical competence when teaching Swedish and if teachers today have the right tools and skills to handle critical literacy on the Internet. The study points to school being an important place for learning critical competence. It is imperative that teachers teach students to navigate on the Internet, to be able to assess the impact media and technology have on their lives and also to review the information they find. One of the problems is that teachers feel insecure about how to handle critical literacy in their everyday teaching. Important tools for this work are knowledge of the different stages in the information seeking process, but also knowledge of how to integrate critical literacy in the classroom. The conclusion is that a great deal has to be done in this area, both at a political level, but also at an educational level. According to the results of this study teachers need more media competence to help students in an ever changing digitalized world.