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Unit: Addition and subtraction

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Possible mastery points

Basic addition and subtraction

Learn
Basic addition
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Basic subtraction
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Practice
Add within 5Get 5 of 7 questions to level up!
Subtract within 5Get 5 of 7 questions to level up!

Addition within 20

Learn
Adding within 20 using place value blocks
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Adding within 20 using ten frames
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Adding 7 + 6
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Adding 8 + 7
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Practice
Add within 20 visuallyGet 5 of 7 questions to level up!
Add within 20Get 5 of 7 questions to level up!

Adding with arrays

Learn
Adding with arrays
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Using arrays in word problems
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Repeated addition: haircuts
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Practice
Adding with arraysGet 3 of 4 questions to level up!
Array word problemsGet 3 of 4 questions to level up!

Subtraction within 20

Learn
Subtract within 20 using a number line
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Subtract within 20 using place value blocks
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Subtract within 20 using ten frames
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Subtracting 14 - 6
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Practice
Subtract within 20 visuallyGet 5 of 7 questions to level up!
Subtract within 20Get 5 of 7 questions to level up!

Addition and subtraction within 20

Learn
Adding within 20 using place value blocks
(Opens a modal)
Adding within 20 using ten frames
(Opens a modal)
Subtract within 20 using place value blocks
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Subtract within 20 using a number line
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Addition and subtraction word problems: gorillas
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Addition and subtraction word problems: superheroes
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Practice
Add & subtract within 20Get 5 of 7 questions to level up!
Add and subtract within 20 word problemsGet 5 of 7 questions to level up!

Quiz 1

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

Addition within 100

Learn
Adding 2-digit numbers without regrouping
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Understanding place value when adding ones
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Understanding place value when adding tens
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Adding with regrouping
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Practice
Add within 100 using place value blocksGet 3 of 4 questions to level up!

Subtraction within 100

Learn
Subtracting 1s using place value
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Subtracting 10s using place value
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Subtracting two-digit numbers without regrouping
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Subtracting 2-digit numbers without regrouping 1
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Subtracting with regrouping (borrowing)
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Practice
Subtract within 100 using place value blocksGet 3 of 4 questions to level up!

Strategies for adding and subtracting within 100

Learn
Breaking apart 2-digit addition problems
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Adding 53+17 by making a group of 10
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Adding by making a group of 10
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Strategies for adding 2-digit numbers
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Addition and subtraction with number lines
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Practice
Break apart 2-digit addition problemsGet 3 of 4 questions to level up!
Add 2-digit numbers by making tensGet 3 of 4 questions to level up!
Select strategies for adding within 100Get 3 of 4 questions to level up!
Add within 100 using a number lineGet 3 of 4 questions to level up!
Subtract within 100 using a number lineGet 3 of 4 questions to level up!

Word problems within 100

Learn
Addition word problem: horses
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Subtraction word problem: tennis balls
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Subtraction word problem: snow
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Subtraction word problem: basketball
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Subtraction word problem: crayons
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Adding and subtracting on number line word problems
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Adding two digit numbers on a number line
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Multi step addition word problem
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Multi-step subtraction word problem
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Practice
Addition word problems within 100Get 3 of 4 questions to level up!
Subtraction word problems within 100Get 3 of 4 questions to level up!
Add and subtract on the number line word problemsGet 3 of 4 questions to level up!
2-step addition word problems within 100Get 3 of 4 questions to level up!
2-step subtraction word problems within 100Get 3 of 4 questions to level up!

Quiz 2

Level up on the above skills and collect up to 1200 Mastery points

Multi-digit addition with regrouping

Learn
Using place value to add 3-digit numbers: part 2
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Adding 3-digit numbers
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Breaking apart 3-digit addition problems
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Addition using groups of 10 and 100
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Relate place value to standard algorithm for multi-digit addition
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Adding multi-digit numbers: 48,029+233,930
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Three digit addition word problems
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Adding four two digit numbers
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Adding multiple 2-digit numbers word problems
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Practice
Add within 1,000 using place value blocksGet 3 of 4 questions to level up!
Add on a number lineGet 3 of 4 questions to level up!
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!
Select strategies for adding within 1000Get 3 of 4 questions to level up!
Add within 1000Get 3 of 4 questions to level up!
Multi-digit additionGet 3 of 4 questions to level up!
Adding up to four 2-digit numbersGet 3 of 4 questions to level up!
Adding up to four 2-digit numbers word problemsGet 3 of 4 questions to level up!

Multi-digit subtraction with regrouping

Learn
Methods for subtracting 3-digit numbers
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Relate place value to standard algorithm for multi-digit subtraction
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Worked example: Subtracting 3-digit numbers (regrouping)
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Worked example: Subtracting 3-digit numbers (regrouping twice)
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Worked example: Subtracting 3-digit numbers (regrouping from 0)
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Subtracting in your head (no regrouping)
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Multi-digit subtraction: 389,002-76,151
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Subtraction by breaking apart
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Missing number for 3-digit subtraction within 1000
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Three digit subtraction word problems
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Practice
Subtract within 1,000 using place value blocksGet 3 of 4 questions to level up!
Subtract on a number lineGet 3 of 4 questions to level up!
Subtract within 1000Get 3 of 4 questions to level up!
Multi-digit subtractionGet 3 of 4 questions to level up!
Break apart 3-digit subtraction problemsGet 3 of 4 questions to level up!
Select strategies for subtracting within 1000Get 3 of 4 questions to level up!

Quiz 3

Level up on the above skills and collect up to 1500 Mastery points
Up next for you:

Unit test

Level up on all the skills in this unit and collect up to 3700 Mastery points!

About this unit

In this topic, we will add and subtract whole numbers. The topic starts with 1+1=2 and goes through adding and subtracting within 1000. We will cover regrouping, borrowing, and word problems.