How to use the Interactive Number Line
- Choose a range. In Settings, pick 0–10, 0–20, 0–100, −10 to 10, tenths, hundredths, quarters, eighths — or set your own start, end and step.
- Pick a start. Click the line where the hops should begin. The point snaps to the nearest tick.
- Hop. Set the hop size with − and +, then click Hop or press + (or Space) to jump forward and − to jump back. The equation builds up above the line. Z undoes a hop.
- Zoom and explore. Drag the line to slide along it; use the mouse wheel or pinch to zoom. Zoom in between two whole numbers to find the tenths and hundredths.
Classroom ideas
- Counting on: start at 8, set the hop size to 2 and let the class predict where each hop lands before you press +.
- Hidden numbers: press H, drop a marker and ask “What number is the marker on?” Click its box to reveal the answer.
- Subtraction as difference: on 0–100, start at 47 and hop forward in tens and ones to 83 — the equation shows the difference.
- Below zero: on −10 to 10, start at 3 and hop back 5 to see why 3 − 5 = −2. Talk about temperatures and floors below ground.
- Fractions are numbers: use the quarters line beside the Fraction Tools to show that 2/4 and 1/2 land on the same point.
Keyboard shortcuts
| + | Hop forward (Space too) |
| − | Hop back |
| Z | Undo the last hop |
| H | Hide or show the numbers |
| M | Switch between hops and markers |
| 0 | Fit the whole range on screen |
| F | Present full screen |
Frequently asked questions
How do I show a jump of more than one?
Change the hop size with the − and + buttons under the line, or type it under Hop size in Settings. On the 0–100 line hops start at 10.
Can I show fractions and decimals?
Yes. Choose tenths or hundredths for decimals, or quarters or eighths for fractions. Fraction labels can read 5/4, 1 1/4, or count every tick (0/4, 1/4 … 4/4).
What happens when I zoom?
The labels re-space themselves so they never overlap. Zoom out and they count in 2s, 5s or 10s; zoom in and halves, tenths and smaller steps appear. Press 0 to fit the whole range again.
How do I quiz the class?
Turn on Hide numbers (or press H). Every label becomes a blank box, and the answer to the equation shows as a question mark. Click a box to reveal it.
Can I put it next to other tools?
Yes. Add it to the Classroom Board — the Math lesson template places it beside the whiteboard.
Updated October 31, 2026 · Free to use in any classroom, no account needed.