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Each game has 10 questions.

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Unlock harder levels by getting an average of 80% or higher.

Earn up to 5 stars for each level

The more questions you answer correctly, the more stars you'll unlock!

Each game has 10 questions.

Green box means correct.

Yellow box means incorrect.

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Grade 2 - Number

Standard 2.N.9 - Practice solving addition sentences up to 20.

Included Skills:

Demonstrate an understanding of addition (limited to 1- and 2-digit numerals) with answers to 100 and the corresponding subtraction by:

• using personal strategies for adding and subtracting with and without the support of manipulatives.

• creating and solving problems that involve addition and subtraction.

• using the commutative property of addition (the order in which numbers are added does not affect the sum).

• using the associative property of addition (grouping a set of numbers in different ways does not affect the sum).

• explaining that the order in which numbers are subtracted may affect the difference.

• Model addition and subtraction, using concrete materials or visual representations, and record the process symbolically.

• Create an addition or a subtraction number sentence and a story problem for a given solution.

• Solve a given problem involving a missing addend, and describe the strategy used.

• Solve a given problem involving a missing minuend or subtrahend, and describe the strategy used.

• Refine personal strategies to increase their efficiency.

• Match a number sentence to a given missing addend problem.

• Match a number sentence to a given missing subtrahend or minuend problem.

• Explain or demonstrate why 5 + 6 = 6 + 5.

• Add a given set of numbers, using the associative property of addition, and explain why the sum is the same; e.g., 2 + 5 + 3 + 8 = (2 + 3) + 5 + 8 or 5 + 3 + (8 + 2).

• Solve a given problem, using horizontal and vertical formats.

• Solve a given problem using the standard/traditional addition algorithm.

• Solve a given problem using the standard/traditional subtraction algorithm.

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