# Number Lines

Canonical: https://manipulatives.org/manipulatives/number-lines/

Lines with equal unit spacing for locating numbers, comparing distance, and representing operations.

![A number line with evenly spaced marks and a highlighted interval](https://manipulatives.org/_astro/number-lines.krrhEqo9.svg)

Published: 2026-10-09
Reviewed: 2026-10-09

Topics: number-sense, operations, fractions

## What they teach

### Order and distance

Locate values relative to zero and compare how far apart they are.

### Operations as movement

Represent addition or subtraction with labeled jumps.

### Fractions and decimals

Divide a unit interval into equal lengths to locate nonwhole numbers.

## How to use them

1. **Establish the scale.** Find two labeled marks and work out what one interval represents.

2. **Locate a value.** Count intervals from a known number, placing the value at a point rather than in a gap.

3. **Explain a journey.** Draw a jump between two points and name the start, change, and finish.

## Try an activity: Two routes to thirty-seven

Start at 18 and add 19. Show one route as +10, then +9. Show another as +20, then −1. Explain why both routes end at 37.

## A unit is a distance

The distance from zero to one is one unit, regardless of how many extra tick marks appear between them. To place quarters, split that unit into four equal intervals. The point at the end of the third interval is three quarters.

Count jumps or intervals, not the starting mark. Moving four units from three means landing on seven. Touching the marks three, four, five, and six counts four marks but only travels three units.

An open number line can show a calculation without having every unit printed. Its labeled jumps must still have clear numerical meanings. If a sketch is not drawn to scale, say so; do not use its visual distances as evidence for which fraction or difference is larger.

## Choose your toolkit

Choose a scale and number range suited to the task. Blank or partly labeled lines allow flexible units; fixed printed lines offer a clear starting reference. The selected number paths count up to 20; use a drawn or extended line for the activity ending at 37 and for fraction investigations.

- [hand2mind Number Path Rekenrek (set of 6)](https://www.amazon.com/dp/B0799J9GZ3) — Six number paths with click-in-place sliders count up to 20. Red and white groups of five support early counting and operations; an activity guide is included.

### Manipulatives app

Use the line to discuss position, order, and distance. Name the unit before comparing jumps. A line drawn on paper is useful when you want to add your own labels or explanations.

[Explore the app](https://apps.apple.com/us/app/manipulatives-hands-on-math/id6780701668)

## Related tools

- [Hundred Charts](https://manipulatives.org/manipulatives/hundred-charts/)
- [Teaching Clocks](https://manipulatives.org/manipulatives/teaching-clocks/)
- [Fraction Tiles](https://manipulatives.org/manipulatives/fraction-tiles/)