Information literacy (IL) involves a group of competences and fundamental skills in the 21st century. Today, society operates around information, which is challenging considering the vast amount of content available online. People must be capable of searching, critically assessing, making sense of, and communicating information. This set of competences must be properly developed since childhood, especially if considering early age access to online resources. To better understand the evolution and current status of IL development and assessment at school (K-12) level, we conducted a systematic literature review based on the guidelines established by the PRISMA statement. Our review led us to an initial set of 1,234 articles, from which 53 passed the inclusion criteria. These articles were used to address six research questions focused on IL definitions, skills, standards, and assessment tools. Our review shows IL evolution over the years and how it has been formalisedthrough definitions and standards. These findings reveal key gaps that must be addressed in order to advance the field further. Keywords: Elementary education, Information literacy, Secondary education, 21st Century abilities.