# Lesson 3 Is it Odd or Even?

Let’s explain why the number of objects in a group is even or odd.

## Warm-up Choral Count: Skip Count by 2

Count by 2, starting at 2.

What patterns do you see?

## Activity 1 Color by Number

Han wants to color a design with the same number of yellow and blue shapes.

Which designs could Han choose? Show your thinking using diagrams, symbols, or other representations. Use counters if it helps.

Draw a circle design that would work for Han and a circle design that would not work.

Priya drew a design that has 6 circles, 3 triangles, and 3 squares. Would Han be able to color it the way he wants? Show your thinking using diagrams, symbols, or other representations. Use counters if it helps.

## Activity 2 Card Sort: Even or Odd

Sort your cards into a group that shows an even number and a group that shows an odd number.

Explain your thinking to your partner.

Find 3 cards that show the same number. Explain to your partner how each card shows whether the number is even or odd in a different way.

## Practice Problem

## Problem 1

For each image, decide whether the number of dots is even or odd. Explain or show your reasoning.