Mathematics textbooks play a critical role in shaping instruction and the ways students and teachers use strategies. Math textbooks are written using language patterns that differ from the narrative patterns many elementary students typically read (Fang & Schleppegrell, 2010; Moje et al., 2012). Mathematical texts rely on a large amount of technical vocabulary. Terms have dual meanings, both general and math specific (Adams, 2003; Thompson, Kersaint, Richards, Hunsader, & Rubenstein, 2008). For example, references to a plane may refer to surface; however, in a story problem, the word plane might refer to an airplane. Absent from the literature are specific studies that represent teachers' ways of reading and thinking about their reading as they use the textbook. This article examines one algebra teacher's changing beliefs about how reading strategies are part of understanding mathematical text and how reading and writing are valuable parts of mathematics instruction. (Contains 2 tables and 4 online resources.)