The importance of social media for today’s youth often elicits teachers to explore educational use of these media. However, many teachers appear to struggle with the tension between possible pedagogical use and the tempting distraction of this technology. The current literature review aims to present a synthesis of conditions and outcomes relevant for a well-considered, evidence-based use of social media, and teacher professional development. A conceptual model consisting of intended curriculum (school level), implemented curriculum (teacher level) and attained curriculum (student level) guided the research questions. The review included 271 articles, which were analysed with framework synthesis. Ambiguous results and poor quality of studies often hindered clear statements about conditions and outcomes regarding social media in the classroom. Nonetheless, reported factors include school culture, attitude towards social media, support, teacher professional development, learning goals and a clear position in the curriculum. Considerations and advice for educational practice were formulated.