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# Unit: Addition and subtraction

#### 0

Possible mastery points

## Relate addition and subtraction

Practice
Relate addition and subtractionGet 5 of 7 questions to level up!

## Addition within 20

Practice
Add within 20 visuallyGet 5 of 7 questions to level up!
Add within 20Get 5 of 7 questions to level up!
Add 3 numbersGet 5 of 7 questions to level up!

## Subtraction within 20

Practice
Subtract within 20 visuallyGet 5 of 7 questions to level up!
Subtract within 20Get 5 of 7 questions to level up!

## Add using arrays

Practice
Adding with arraysGet 3 of 4 questions to level up!
Array word problemsGet 3 of 4 questions to level up!

## Equal sign

Practice
Equal signGet 5 of 7 questions to level up!

#### Quiz 1

Level up on the above skills and collect up to 1000 Mastery points

## Missing number within 20

Learn
No videos or articles available in this lesson
Practice
Find missing number (add and subtract within 20)Get 5 of 7 questions to level up!

## Word problems within 20

Practice
Addition and subtraction word problems 1Get 5 of 7 questions to level up!
Addition and subtraction word problems 2Get 5 of 7 questions to level up!
Add and subtract within 20 word problemsGet 5 of 7 questions to level up!

## Word problems with "more" and "fewer"

Practice
Add and subtract within 20 word problemsGet 5 of 7 questions to level up!
Word problems with "more" and "fewer" 2Get 5 of 7 questions to level up!

#### Quiz 2

Level up on the above skills and collect up to 600 Mastery points
Up next for you:

#### Unit test

Level up on all the skills in this unit and collect up to 1600 Mastery points!

### About this unit

First, we will learn how addition and subtraction relate. Next, we will add and subtract numbers less than or equal to 20 and solve addition and subtraction word problems. Finally, we will begin adding 2-digit numbers.