Number Line Detective Worksheet

Name: _______________ Date: _______________

Instructions: Use what you know about equal spacing and unit intervals to solve each problem. Show your work on the number lines below. You may use extra Blank Number Line Templates if you need more space.

1. Fill in the Missing Numbers

0 ──┬──┬──┬──┬──┬──┬──┬──┬──┬──10

2. Detective Question

Which number is halfway between 2 and 6 on this number line? Explain your thinking.

2 ──┬──┬──┬──6

3. Draw & Label

On the blank line below, draw and label a number line from 5 (left end) to 15 (right end). Divide it into 10 equal spaces and label every point.

4. Unit Steps

Which number is 3 units to the right of 7? Draw a small number line, start at 7, make 3 equal jumps, and label the end point.

5. Extension Challenge

If our number line goes from 0 to 20, where would 15 be? Draw the line, label 0, 20, and 15, and explain why your spacing is correct.

Number Line Anchor Chart

What Is a Number Line?

• A straight line that shows numbers in order from smallest to largest
• Helps us understand how far apart numbers are
• Uses equal spaces (intervals) to represent each unit step

Key Vocabulary

• Interval: The space between two adjacent points on the line
• Unit: One equal part of the interval
• Endpoint: The first or last point on the number line (e.g., 0 and 10)

Steps to Draw and Label a Number Line

1. Draw a horizontal line and add arrows on both ends if you want it to extend beyond your numbers.
2. Mark your endpoints: Label the leftmost point (start) and rightmost point (end) with the numbers given (e.g., 0 and 10).
3. Divide into equal intervals: Count how many spaces you need (for 0–10, you need 10 intervals). Draw ticks (│) and count aloud as you mark each one.
4. Label each point: Starting at the left endpoint, write each whole number in order at each tick mark (0, 1, 2, …, 10).
5. Check your spacing: Make sure all spaces between ticks look the same size—this keeps each unit equal.

Detective Clues & Tips

• Look for the number of intervals first, then divide your line equally.
• If you’re placing a number halfway between two points, count the spaces (intervals) and go to the middle.
• Use a ruler or straightedge for clear, even intervals.

Extension Challenge

“If our number line goes from 0 to 20, how many intervals do we need? Where would 15 go? Draw and label!”

Blank Number Line Templates

Use these blank number lines to draw, divide into equal intervals, and label your numbers. Each line has arrows on both ends to show it can extend.

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