# Clip 26/29: Day 2: Decimal Post-Lesson Debrief Part D

## Overview

Mia Buljan and Erika Isomura discuss the “culture of the math class,” in which all of the explanations are embedded in shared experience and language.

Erika recounts various examples in which her students realize that their learning is related to prior experiences they’ve had; students “understand the idea of what we’ve done in the past, because it will help us with what we’re going to do in the future.”

Mia and Erika connect this culture-building work to the Common Core State Standards for Mathematical Practice and to the patience required of both teachers and students in developing this mathematical culture.

Erika explains her rationale for using expressions and grids in representing fractional and decimal quantities, focusing on particular student groups’ work that day. Erika considers the “puzzle” of understanding student pairs’ choices around which cards to use to begin the card sort, and describes what she heard students give as support for their reasoning.

Mia connects the students’ work to Standard for Mathematical Practice 7 (“Look for and make use of structure”), as students are looking at the underlying mathematical structures of whole numbers.

Erika emphasizes her overall goal of wanting to have students arrive at understanding mathematical operations without necessarily teaching them explicitly.