An after-school book club, led by the school librarian, was held to test the efficacy of the peritextual literacy framework (PLF) in teaching skills related to critical thinking, problem solving, information literacy, and media literacy. The PLF is an extension of paratext theory developed by Gérard Genette, which provides a typology of the functions of peritext; this extension results in a framework that can be used for research or as a scaffold for teaching. Twelve middle school students met once a month for five months to apply the PLF to an analysis of science, technology, engineering, art, and math (STEAM) texts. The participants enjoyed the club and were able to demonstrate their ability to use peritextual elements to think critically about STEAM-related nonfiction books. Students were able to discuss how the functions of peritext affected their motivation to read a text and their ability to retrieve information from a text, and how peritext functions might affect their opinion of the credibility of information presented in a book.