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Unit 11: Operations and Algebra < 159

1,500 possible mastery points
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Quiz
Unit test

Relate addition and subtraction

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Practice

Addition within 20

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Practice

Subtraction within 20

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Practice

Quiz 1

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

Add using arrays

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Practice

Add and subtract within 20

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Practice

Quiz 2

Level up on the above skills and collect up to 240 Mastery points

Equal sign

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Practice

Missing number within 20

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  • No videos or articles available in this lesson

Practice

Word problems within 20

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Practice

Quiz 3

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

Word problems with "more" and "fewer"

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Practice

Quiz 4

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

Unit test

Level up on all the skills in this unit and collect up to 1,600 Mastery points!