# Lesson 3 Count to Add and Subtract

Let’s solve story problems.

## Warm-up Choral Count: Forward and Backward

Let’s start at 20 and count backward to 1.

## Activity 1 Ride the Bus

There were 7 people on the bus.

Then 1 more person got on the bus.

How many people are on the bus now?Show your thinking using objects, drawings, numbers, or words.

There were 10 people on the bus.

Then 1 person got off the bus.

How many people are on the bus now?Show your thinking using objects, drawings, numbers, or words.

## Activity 2 Singing Students

students were singing.

Then 1 more student came to sing with them.

How many students are singing now?Show your thinking using objects, drawings, numbers, or words.

students were singing.

Then 1 student stopped singing and went home.

How many students are singing now?Show your thinking using objects, drawings, numbers, or words.

## Activity 3 Centers: Choice Time

Choose a center.