# Lesson 2

Explore Expressions and Sums

### Lesson Purpose

The purpose of this lesson is to write addition expressions within 10 and find the sums.

### Lesson Narrative

This lesson builds on the previous lesson as students were asked to determine the sum of two dot cubes. It also builds on the work of kindergarten, where students wrote addition expressions to represent images and situations. In this lesson, students match expressions to dot images before they are asked to write addition expressions (MP2). Students also continue to build their math language related to the sums, addition expressions, and mathematical community (MP6).

Math Community
Tell students they will have an opportunity to revise their math community ideas at the end of this lesson, so as they work today they should think about actions that may be missing from the current list.

• Engagement
• MLR8

### Learning Goals

Teacher Facing

• Write addition expressions within 10 based on images and add in a way that makes sense to them.

### Student Facing

• Let’s write addition expressions and find the sum of two numbers.

### Required Materials

Materials to Gather

Materials to Copy

• Number Cards (0-10)
• Check It Off Stage 1 Recording Sheet Grade 1

### Required Preparation

Activity 2:

• Create a set of cards from the blackline master for each group of 2.

Building On

### Lesson Timeline

 Warm-up 10 min Activity 1 15 min Activity 2 20 min Lesson Synthesis 10 min Cool-down 5 min

### Teacher Reflection Questions

How are you facilitating the creation of a productive Mathematical Community? Where can you point to evidence of this for students to see?

### Print Formatted Materials

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