# Lesson 3

¿Es par o impar?

### Lesson Purpose

The purpose of this lesson is for students to determine whether representations of groups of objects show an even or odd number of objects.

### Lesson Narrative

In a previous lesson, students learned the terms even and odd and saw that if a group has an even number of objects, it can be separated into two equal groups and that each object can be paired with another object.

In this lesson, students justify why a number is even or odd using methods based on making two equal groups, pairing objects, or skip-counting by 2. Some students may begin to justify why a group of objects has an even or odd number of members by using equations with two equal addends to represent even numbers of objects. In the second activity, they interpret addition equations in this way and connect the equations to representations of 2 equal groups (MP2).

• Action and Expression

Activity 2: Clasificación de tarjetas: Par o impar

### Learning Goals

Teacher Facing

• Determine whether representations of groups of objects show an even or odd number of objects.

### Student Facing

• Expliquemos por qué el número de objetos de un grupo es par o impar.

### Required Materials

Materials to Gather

Materials to Copy

• Even and Odd Card Sort

### Required Preparation

Activity 1:

• Each group of 2 needs access to counters and blue and yellow crayons or colored pencils.

Activity 2:

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

Building Towards

### 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

Reflect on whose thinking was heard today. Reflect on whose thinking was not heard but could have enriched the conversations. What prompts or structures might better enable the latter to share their voices and reasoning?

### Suggested Centers

• Target Numbers (1–5), Stage 7: Subtract Hundreds, Tens, or Ones (Supporting)
• Five in a Row: Addition and Subtraction (1–2), Stage 8: Add within 1,000 with Composing (Supporting)
• How Close? (1–5), Stage 4: Add to 1,000 (Supporting)