“…Blending theories in this way was first seen in Cobb, Yackel, and Wood's work (1992) and continues today (Cobb, 2007;Dweck, 2015;Galbraith, Stillman, & Brown, 2010, Goos & Williams, 2013Hennessey, Higley, & Chesnut, 2012;Lerman, 2013;Rasmussen & Stephan, 2008;Schwarz, Dreyfus, & Hershkowitz, 2009;Simon, 2013;Stillman, Cheung, Mason, Sheffield., Bharatah, & Ueno, 2009;Tomasello, Carpenter, Call, Behne, & Moll, 2005;Williams & Huang, 2014). The evolution of and blending of these learning theories have led organizations such as the National Council of Teachers of Mathematics (NCTM), the National Science Foundation (NSF), and the National Research Council (NRC) to suggest that mathematics instruction should shift from the current "traditional" methodologies that focus on procedure and memorization to those that incorporate interactions between and among teachers, students, and content (Stigler & Hiebert, 2004;Cohen, Raudenbush, & Ball, 2003;Jacobs, Lamb, & Phillipp, 2010;Wood, 1993) while emphasizing important mathematics ideas, evidence-based argument, social construction of mathematics, and sense-making (Billings & Fitzgerald, 2002;Corey, Peterson, Lewis, & Bukarau, 2010;Hennessey, Higley, & Chesnut, 2012;Murphy & Mason, 2006).…”