“…National reform efforts (e.g., Common Core Initiative, Race to the Top) direct attention toward the effectiveness of teachers and their role in reversing poor mathematics achievement among American students. There is no doubt that teachers play a critical role in students' mathematics learning and achievement (Chetty, Friedman, & Rockoff, 2011;Darling-Hammond, 2002;Hiebert & Grouws, 2007;Nye, Konstantopolous, & Hedges, 2004;Rowan, Correnti, & Miller, 2002). Teachers produce changes in students' achievement through the quality of classroom instructional interactions, including their selection of instructional tasks and opportunities afforded to students (Charalambous, 2010;Kilpatrick, Swafford, & Findell, 2001;Stein, Smith, Henningsen, & Silver, 2000).…”