The mathematics education community has affirmed the importance of writing in the mathematics classroom for a long time (e.g., National Council of Teachers of Mathematics [NCTM], 2000, 2014), and many examples exist of writing strategies or activities in mathematics learning (e.g., Altieri, 2009; Bixby, 2018; Carter, 2009; Gunter, 2016; Linhart, 2014; Pugalee, 2001; Staal & Wells, 2015; Yang, 2005). Although elementary school students likely use writing fluidly and frequently while learning mathematics, secondary students may connect the idea of writing in mathematics only with writing numbers and equations. Regardless of their experience level, many students find sharing their mathematical thinking in words to be challenging. Just as with any routine teachers introduce into their classroom, they should begin by suggesting it with regularity and holding high expectations for the result (NCTM, 2000). To do this, teachers must first craft an environment in which writing is possible. In each of the classrooms whose tasks will be shared in this article, the teachers have created spaces where shared meaning-making is valued by explicitly including their students in the process of the "decisions they make, the conversations they orchestrate, and the physical setting they create" (NCTM, 2000, p. 18).