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Unit: Addition and subtraction within 100

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Possible mastery points

About this unit

In this unit, you'll learn about adding and subtracting numbers within 100. But don't worry, we're going to make it super fun. You'll practice skip counting by 5s and 10s, use colorful place value blocks, and explore number lines. Plus, you'll solve cool word problems and even some 2-step challenges.

Skip-counting

Learn

Practice

Skip-count by 5sGet 5 of 7 questions to level up!
Skip-count by 10sGet 5 of 7 questions to level up!

Adding 1s and 10s

Learn

Practice

Add 1 or 10Get 5 of 7 questions to level up!
Add 1s or 10s (no regrouping)Get 5 of 7 questions to level up!

Subtracting 1s and 10s

Learn

Practice

Subtract 1 or 10Get 5 of 7 questions to level up!
Subtracting 1s or 10s (no regrouping)Get 5 of 7 questions to level up!

Quiz 1

Level up on the above skills and collect up to 480 Mastery points

Intro to addition with 2-digit numbers

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Practice

Adding up to four 2-digit numbersGet 3 of 4 questions to level up!
Break apart 2-digit addition problemsGet 3 of 4 questions to level up!
Regroup when adding 1-digit numbersGet 5 of 7 questions to level up!

Intro to subtraction with 2-digit numbers

Learn

Practice

Subtract 1-digit numbers with regroupingGet 5 of 7 questions to level up!

Strategies for adding and subtracting within 100

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Practice

Add 2-digit numbers by making tensGet 3 of 4 questions to level up!
Add 2-digit numbers by making tens 2Get 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!

Quiz 2

Level up on the above skills and collect up to 720 Mastery points

Addition within 100

Learn

Practice

Add within 100 using place value blocksGet 3 of 4 questions to level up!

Subtraction within 100

Learn

Practice

Subtract within 100 using place value blocksGet 3 of 4 questions to level up!

Quiz 3

Level up on the above skills and collect up to 160 Mastery points

Word problems within 100

Learn

Practice

Add and subtract on the number line word problemsGet 3 of 4 questions to level up!
Addition word problems within 100Get 3 of 4 questions to level up!
Subtraction word problems within 100Get 3 of 4 questions to level up!

Word problems with "more" and "fewer" (within 100)

Learn

Practice

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 4

Level up on the above skills and collect up to 400 Mastery points

Addition and subtraction missing value problems

Learn

Missing numbers in addition and subtraction
(Opens a modal)

Practice

Find the missing number (add and subtract within 100)Get 3 of 4 questions to level up!

Up next for you:

Unit test

Level up on all the skills in this unit and collect up to 2300 Mastery points!