In this webinar, we will share part of the Read.Inquire.Write. curriculum for teaching inquiry in middle school social studies that support students' critical thinking and argument writing. We will highlight the Bookmark Tool, one of the "disciplinary literacy tools" we developed with teachers that support a wide range of students (including English learners and below-grade readers) in becoming proficient in reasoning and writing with sources. The Bookmark Tool is embedded in investigations that provide students with opportunities to engage in inquiry with and construct their own arguments. We will share specific instructional materials from a middle school world history and geography investigation focused on child labor. This webinar will be of interest to anyone interested in implementing the C3 Framework, integrating the Common Core State Standards for ELA and literacy into subject matter instruction, and/or working effectively with English learners and other students who struggle with reading.