# Lesson 2

Relacionemos la suma y la resta

### Lesson Purpose

The purpose of this lesson is for students to use the relationship between addition and subtraction to fluently add and subtract within 10.

### Lesson Narrative

Throughout the year students have been building fluency with addition and subtraction within 10. Students often find subtraction more difficult than addition because it does not relate to counting as clearly. The purpose of this lesson is to highlight and have students utilize the relationship between addition and subtraction (MP7) and for students to practice differences within 10 that they do not yet know with fluency.

If students need additional support with the concepts in this lesson, refer back to Unit 3, Section A in the curriculum materials.

• Representation
• MLR2

### Learning Goals

Teacher Facing

• Develop fluency with addition and subtraction within 10, using the relationship between addition and subtraction.

### Student Facing

• Examinemos la relación que hay entre la suma y la resta.

### Required Materials

Materials to Gather

### Required Preparation

Activity 1:

• Create a tower of connecting cubes with 4 cubes of one color and 3 cubes of another color.

### Lesson Timeline

 Warm-up 10 min Activity 1 15 min Activity 2 10 min Activity 3 10 min Lesson Synthesis 10 min Cool-down 5 min

### Teacher Reflection Questions

Students will continue to use the relationship between addition and subtraction to add and subtract in upcoming grades. In what ways did you see students use their understanding of the relationship between addition and subtraction during today's lesson? How can you continue to foster this understanding in upcoming lessons?