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Early Math (Grade K–2)

Interactive Number Line to 20

An essential early math visualizer to help young learners master counting to 20, single and double digit addition, and subitizing strategies.

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K–2 Math Strategies

Teaching Addition & Subtraction with a 0 to 20 Number Line

The interactive number line to 20 is a fundamental virtual manipulative in primary mathematics classrooms. It moves children away from finger-counting toward visual numerical reasoning:

Make a 10 Strategy

Model how to add 8 + 6 by jumping +2 to reach 10, then jumping +4 to land on 14.

Counting On & Back

Students start at a larger number and jump forward for addition or backward for subtraction equations up to 20.

Mystery Cover Cards

Cover missing numbers on the 1–20 line to practice missing addends and number sequence recall.