# Lesson 3

Add 1 or 2

### Lesson Purpose

The purpose of this lesson is for students to add within 10 when one addend is 1 or 2.

### Lesson Narrative

This lesson builds on the understanding developed in kindergarten, that each successive number name refers to a quantity that is one larger. Students relate addition to counting and see that adding one or two more is the same as counting one or two more (MP8). This deepens their understanding of the structure of the counting sequence (MP7).

Center Choice Time is introduced for the first time in this lesson. During center choice times, students choose the activities they would like to do, choosing from previously introduced center activities. Although there are four centers to choose from in this lesson, not all centers need to be offered at this time. This is an opportunity to introduce classroom structures that will be used during center time throughout the year.

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
• MLR7

### Learning Goals

Teacher Facing

• Add within 10, given expressions with an addend of 1 or 2, in a way that makes sense to them.

### Student Facing

• Let’s add 1 or 2.

### Required Materials

Materials to Gather

Materials to Copy

• Five in a Row Addition and Subtraction Stages 1 and 2 Gameboard

### Required Preparation

Activity 1:

• Each group of 2 needs a set of Number Cards 0–10.

Activity 2:

• Gather materials from previous centers:
• Counting Collections, Stage 1
• Number Race, Stage 3
• Check it Off, Stage 1
• Five in a Row: Addition and Subtraction, Stage 1

Building On

### Lesson Timeline

 Warm-up 10 min Activity 1 20 min Activity 2 20 min Lesson Synthesis 10 min Cool-down 0 min

### Teacher Reflection Questions

Reflect on whether or not you were able to circulate and hear student thinking while students worked in centers. If you were, what routines or structures helped students work independently? If you were not, what routines or structures can you establish to ensure that you are able to circulate and talk to students as they work?

### Print Formatted Materials

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