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.

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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Math Games for Teachers

Grade 1 - Number

Standard 1.N.10 - Complete the subtraction sentence by filling in the missing number with operands up to 18.

Included Skills:

Describe and use mental mathematics strategies (memorization not intended), such as:
counting on and counting back
making 10
doubles
using addition to subtract
to determine the basic addition facts to 18 and related subtraction facts.

Achievement Indicators
(It is not intended that students recall the basic facts but become familiar with strategies to mentally determine sums and differences.)
- Use and describe a personal strategy for determining a given sum.
- Use and describe a personal strategy for determining a given difference.
- Write the related subtraction fact for a given addition fact.
- Write the related addition fact for a given subtraction fact.

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