# Section A: Practice Problems Add and Subtract within 10

## Section Summary

Details

We practiced counting collections.

We added 1 or 2 by counting on. 4…5, 6

We subtracted 1 or 2 by counting back. 6…5, 4

We played games with addition and subtraction within 10.

## Problem 1 (Pre-Unit)

Color in the shapes that are triangles.

## Problem 2 (Pre-Unit)

How many do you see?

## Problem 3 (Pre-Unit)

Match the pictures with the expressions.

## Problem 4 (Lesson 1)

How many do you see?

## Problem 5 (Lesson 2)

Circle the expression that matches the dots.

## Problem 6 (Lesson 2)

Circle the dots that match the expression:

## Problem 7 (Lesson 3)

Find the value of each sum.

## Problem 8 (Lesson 4)

Find the value of each difference.

## Problem 9 (Lesson 5)

Show 2 ways you could use these cards in the game.

## Problem 10 (Exploration)

Materials needed:

• Number cards 2–10

• Two dot cubes

Directions:

1. Choose a number card. Show 2 numbers on the dot cubes that add to make your number.

2. Can you show another way?

## Problem 11 (Exploration)

Partner A: Hold up some fingers on each hand.

Partner B: Fill in the blanks to show how many:

Switch roles and play again.