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# Unit: Addition, subtraction, and estimation

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#### 0

Possible mastery points

## Rounding to nearest 10 or 100

Practice
Round to nearest 10 or 100 on the number lineGet 5 of 7 questions to level up!
Round to nearest 10 or 100Get 3 of 4 questions to level up!
Round to nearest 10 or 100 challengeGet 3 of 4 questions to level up!

#### Quiz 1

Level up on the above skills and collect up to 300 Mastery points

## Estimate to add multi-digit numbers

Practice
Estimate to add multi-digit whole numbersGet 3 of 4 questions to level up!

## Strategies for adding two and three-digit numbers

Practice
Break apart 3-digit addition problemsGet 3 of 4 questions to level up!
Add using groups of 10 and 100Get 3 of 4 questions to level up!
Add on a number lineGet 3 of 4 questions to level up!
Select strategies for adding within 1000Get 3 of 4 questions to level up!

## Adding with regrouping within 1000

Practice
Add within 1000Get 3 of 4 questions to level up!

#### Quiz 2

Level up on the above skills and collect up to 600 Mastery points

## Estimate to subtract multi-digit numbers

Practice
Estimate to subtract multi-digit whole numbersGet 3 of 4 questions to level up!

## Strategies for subtracting two and three-digit numbers

Practice
Break apart 3-digit subtraction problemsGet 3 of 4 questions to level up!
Subtract on a number lineGet 3 of 4 questions to level up!
Select strategies for subtracting within 1000Get 3 of 4 questions to level up!

## Subtracting with regrouping within 1000

#### Quiz 3

Level up on the above skills and collect up to 500 Mastery points

Practice

## Addition and subtraction word problems

Practice
Add and subtract within 1000 word problemsGet 3 of 4 questions to level up!

#### Quiz 4

Level up on the above skills and collect up to 200 Mastery points
Up next for you:

#### Unit test

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