This two-semester pedagogical study investigated the effectiveness of an approach to information and media literacy instruction for elementary preservice teachers. Participants were trained in and then used a systematic process of searching for, evaluating, and using journal articles and websites. Two-thirds of the Semester one participants were unsuccessful identifying relevant, high-quality journal articles and ½ inaccurately evaluated the quality of websites. After three opportunities for formative assessment were added to the instruction model in Semester two, participants proficiently evaluated websites and ¾ were able to find relevant journal articles. The results demonstrate the importance of formative assessment and the need to provide preservice teachers with information and media literacy training so they are better able to navigate and evaluate digital-age resources in order to expand their content mastery and teach their students 21st century skills.