Measuring with Non-Standard Units

For Elementary Students

What are Non-Standard Units?

Non-standard units are everyday objects you use to measure things — not official tools like rulers or scales.

Think about it like this: Before rulers were invented, people measured with their feet, hands, and other objects they had!

Why Use Non-Standard Units?

To learn about measurement before using rulers

To practice comparing sizes

When you don't have measuring tools handy

To understand that measurement is about comparing!

Measuring Length

Length is how long something is.

Using Paperclips

Example: "How long is the pencil?"

Line up paperclips end-to-end along the pencil:

Pencil: |__________________|

📎📎📎📎📎📎 (6 paperclips)

Answer: The pencil is 6 paperclips long.

Using Hands (Hand Spans)

Place your hand flat, thumb to pinky stretched out. That's one hand span.

Example: "How wide is the desk?"

Desk: |__________________________|

[hand][hand][hand][hand] (4 hand spans)

Answer: The desk is 4 hand spans wide.

Using Feet (Footsteps)

Example: "How long is the hallway?"

Walk heel-to-toe and count your steps:

👣 👣 👣 👣 👣 👣 👣 👣 👣 👣 (10 steps)

Answer: The hallway is 10 feet long (using your feet as the unit!).

Important Rule: Use the Same Unit

You can't mix different units!

❌ Wrong: "The table is 3 paperclips and 2 hands long."

✓ Right: "The table is 8 paperclips long" OR "The table is 2 hands long."

Pick one unit and stick with it!

Measuring Weight

You can compare which is heavier by holding objects!

Example: "Is the book heavier than 5 crayons?"

Hold the book in one hand, 5 crayons in the other. Which feels heavier?

Measuring Capacity (How Much Holds)

Capacity is how much a container holds.

Example: "How many cups of water fill the bowl?"

Pour cups of water into the bowl until it's full. Count how many cups you used.

Answer: "The bowl holds 4 cups of water."

For Junior High Students

Why Non-Standard Units Matter

Using non-standard units teaches:

Measurement concept — comparing one thing to another

The need for standard units — everyone's hand is a different size!

Estimation skills — getting a sense of size

The Problem with Non-Standard Units

Different people get different answers!

Example: Measure a table using hand spans.

• Student A (small hands): Table is 6 hand spans
• Student B (large hands): Table is 4 hand spans

Who's right? Both! But the measurements don't match because the unit size is different.

This is why we use standard units (inches, feet, centimeters) that are the same for everyone.

Choosing Good Non-Standard Units

Pick units that:

Match the size of what you're measuring

• Use paperclips for small things (pencils, books)
• Use footsteps for big things (rooms, hallways)

Are consistent in size

• All paperclips should be the same size
• All footsteps should be heel-to-toe (not random)

Don't overlap or have gaps

• Line them up carefully end-to-end

Estimating First, Then Measuring

Good practice:

Step 1: Estimate ("I think the book is about 10 paperclips long")

Step 2: Measure (actually line up paperclips)

Step 3: Compare ("I was close! It's actually 9 paperclips.")

This builds estimation skills!

Recording Non-Standard Measurements

Always write what unit you used!

Good: "The desk is 12 hands wide."

Bad: "The desk is 12." (12 what??)

Converting Between Non-Standard Units

If you know how units relate, you can convert!

Example: 1 hand span = 3 paperclips (approximately)

If the book is 6 paperclips long, how many hand spans?

6 paperclips ÷ 3 = 2 hand spans

Transitioning to Standard Units

Once you understand measurement with non-standard units, standard units make more sense!

Non-standard → Standard:

Real-World Applications

Ancient measurements used body parts:

• Cubit — length from elbow to fingertip
• Foot — length of a foot (where the unit name comes from!)
• Yard — nose to fingertip with arm outstretched

Modern informal measurements:

• "The fish was about a ruler long."
• "The room is 10 steps across."
• "The package weighs about 3 books."

Activity Ideas

Measure your classroom:

• Length in footsteps
• Width in arm lengths
• Height in students standing on each other (just kidding!)

Measure yourself:

• Height in hands
• Arm span in paperclips

Compare:

• Does everyone get the same answer?
• Why or why not?

Understanding Precision

Non-standard units are less precise than standard units.

Example:

• "The table is 3 hands wide" — could be anywhere from 21–27 inches depending on hand size
• "The table is 24 inches wide" — exact!

When precision matters (building, science), use standard units.

When estimation is OK (quick check, rough idea), non-standard works!

Practice