← Little Scientists MathsMeasuring with units15 minutesStd 1–2

Measure With Your Hand

✨ You and a grown-up measure the very same table and get two completely different numbers.

The same table edge shown twice: divided into nine small child handspans and into six larger grown-up handspans, with a shared paper strip below showing why everyone needs the same unit. — How it works

🧰 You need

your own hand
a table and a doorway to measure
a paper strip
a pencil
a grown-up's hand to compare

👀 What you will see

Your handspan count is bigger than the grown-up's count for the very same table. When two people use the same paper strip, they agree. The number depends on the size of the unit you choose.

🧪 Do it

Open your hand wide and step it along the table edge, counting each span.
Write down the number of handspans.
Ask a grown-up to measure the same edge with their hand and write that number too.
Compare the two numbers and talk about why they differ.
Cut a paper strip exactly as long as your handspan.
Measure the doorway with the paper strip and check that a friend using the same strip gets your number.

💡 Why it happens

Measuring means counting how many of a chosen length fit into the thing you are measuring, and that chosen length is called a unit. A small unit gives a big number and a big unit gives a small number, even though the table never changed. Because everybody's hand is a different size, people all over the world agreed to share fixed units like the centimetre and the metre. That way a number measured in one country still means the same thing in another.

🔁 Now try this

Measure the same table in handspans and in footsteps, then work out which unit needed fewer counts.

🤔 Think about it

Why do shops not sell cloth by the handspan?

🧘 Ask the Acharya

“Why do shops not sell cloth by the handspan?” — ask him and he will explain it from your own chapters.

Ask Guru →

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