# Clip 9/20: Problem 2 - Part A

## Overview

Jacob Disston asks his students to describe and categorize their symbol strings.

## Teacher Commentary

COMMENTARY BY COACH LINDA FISHER: This section just takes students to a deeper level of noticing. The lesson keeps recycling or layering the ideas, forcing students to new levels of describing and deciphering the symbol strings. There is something so important in the act of sorting and classifying. I find the students are now much more talkative than at the beginning of the lesson. They seem more invested in the reaching an understanding and questioning each other. What evidence do you see of their thinking progressing over the course of the lesson?