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.

More Ways To Use Math Games
Game Quickplay
Video Help

Need some help or instruction on how to do this skill?

Offline Worksheets

Want a paper copy? Print a generated PDF for this skill.

Top Mathematicians Leaderboards

See how you scored compared to other students from around the world.

Start a MathJam

Learn Math Together.

Math Games for Teachers

Grade 1 - The Number System

Standard 1.NS.1.10 - Complete the subtraction sentence by filling in the missing number with operands up to 18.

Included Skills:

Students will be expected to use and describe strategies to determine sums and differences using manipulatives and visual aids. Strategies include
counting on or counting back
one more or one less
making ten
doubles
near doubles

Performance Indicators
- N10.01 Use and describe a personal strategy to determine a sum.
- N10.02 Use and describe a personal strategy to determine a difference.
- N10.03 Use and describe how two different strategies can be used to determine a sum or difference.

If you notice any problems, please let us know.