# Section A: Practice Problems Count to Add and Subtract

## Section Summary

## Details

In this section, we counted two groups of things to figure out how many there are altogether.

3 yellow counters and 4 red counters is 7 counters.

3 and 4 is 7.

We added more things and found out how many there were altogether.

There were 5 counters on the 5-frame and we added 4 more counters.

5 and 4 is 9.

We subtracted, or took away, some things and figured out how many were left.

There were 5 counters on the 5-frame and we took away 2 of them.

5 take away 2 is 3.

## Problem 1 (Lesson 2)

There are squares.

There are triangles.

There are shapes.

## Problem 2 (Lesson 3)

There are shapes.

There are squares.

There are triangles.

## Problem 3 (Lesson 4)

Count out 4 counters.

Add 1 more.There are counters.

Count out 6 counters.

Add 1 more.There are counters.

Count out 8 counters.

Add 1 more.There are counters.

## Problem 4 (Lesson 5)

Count out 8 counters.

Take away 2 counters.There are counters.

Count out 6 counters.

Take away 2 counters.There are counters.

Count out 4 counters.

Take away 2 counters.There are counters.

## Problem 5 (Exploration)

Start with a full 5-frame.

Player 1 rolls a cube on the number mat and takes away or adds that number of counters while player 2 is not looking.

Then player 2 figures out what player 1 did.

Players take turns switching roles.

## Problem 6 (Exploration)

Roll a cube onto a number mat.

Count out that number of counters.

Roll a cube again onto the number mat.

Count out that number of counters.

How many counters do you have in all?

## Problem 7 (Exploration)

Pick a number from the list to put in the blank space.

2

7

6

3

Then try the problem you made.

Count out 8 counters.

Take away counters.

How many counters are left?After you try the problem you made, try it again with a different number in the blank space.

Do you think your answer will be the same or different?

Explain.