Standards-based mathematics instruction [SBMI], with opportunities to engage in high-quality mathematical discourse about meaningful tasks, leads to increased student achievement. However, not all students participate in mathematical discourse with high-quality. Esmonde & Langer-Osuna (2013) found that students participate in discourse with various degrees of engagement based upon individual beliefs. Boaler (2006b) found that SBMI in a detracked setting improves students’ beliefs about mathematics. The purpose of this descriptive case study was to illustrate the phenomenon of incongruent written curricula commitments across grade bands in a school district by examining small-group discourse and students’ mathematical related beliefs. This study compared students’ mathematical related beliefs across two schools in the same district and small-group discourse across four classrooms within those two schools. Analyzing small-group discourse quality through the lens of students’ beliefs and the degree to which lessons were representative of SBMI illuminated the interconnectivity of discourse, beliefs, and the instructional model.