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Each game has 10 questions.

Green box means correct.

Yellow box means incorrect.

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 - Simplify both sides of the equation. Fill in the missing number with sums up to 20 to make the equation true.

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

• explaining that the order in which numbers are added 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 solution.

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

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

• Match a number sentence to a missing addend problem.

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

• Add a set of numbers in two different ways, and explain that the sum is the same (e.g., 2 + 5 + 3 + 8 = 2 + 3 + 5 + 8 or 5 + 3 + 8 + 2).

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