Examination of social annotation during assigned readings in this study brings together research about digital reading, learning communities, metacognition, and critical literacy. Social annotation allows readers to engage with text collaboratively to build understanding during reading. The authors conducted a content analysis of over 400 annotations made by 12 novice teachers to discover their metacognitive, social, and critical practices during reading. Findings suggest that text-to-text connections are a powerful practice for developing contextual knowledge, that practice-based identities enacted by participants during reading further supported their knowledge development, and that metacognition and strategy instruction are essential for critical literacy development.