For curious kids aged 5–8 · 16 pages of measuring fun!
Hi there! I'm Remy the Ruler 📏 — and I love measuring things!
Do you ever wonder how long a pencil is? Or how tall your favourite toy stands? Or how wide your book is?
That's what measuring is all about! Measuring helps us find out exactly how long something is.
We use special tools to measure. The most popular one is the ruler — that flat stick with numbers on it!
Ready to learn how to use me? Let's go! 🚀
Length is how long something is — from one end to the other end!
You can measure the length of lots of things:
🖊️ A pencil
📚 A book
🐛 A worm
🛏️ Your bed
😊 Even your smile!
We measure length using units. The most common units are centimetres (cm) and metres (m).
Short things use centimetres — like a pencil. Really long things use metres — like a swimming pool!
Which unit would you use to measure a pencil?
Before we start measuring, let's get to know the ruler! Tap each part on the ruler below to learn what it does!
Measuring with a ruler is easy if you follow these 3 steps! Tap each step to see it in action!
Remy wants to measure his pencil. Watch how he does it! Drag the ruler to line it up with the pencil and measure it!
We measure in centimetres (cm) for small things and metres (m) for big things!
🔢 100 centimetres = 1 metre
Imagine 100 ants lined up in a row — that would be about 1 metre! 🐜×100
Your ruler shows centimetres. For metres, you'd use a measuring tape — the long stretchy one!
Here's a trick to remember:
cm = small things (pencil, eraser, leaf)
m = big things (door, car, classroom)
| 📏 Centimetres (cm) | ✏️ Pencil, 🍎 Apple, 📱 Phone, 📚 Book | Small things! |
| 📐 Metres (m) | 🚪 Door, 🏊 Pool, 🚗 Car, 🌳 Tree | Big things! |
Pick an object below and drag the ruler to measure it! Try all 5 objects!
Remy is at the market and needs to know which things are bigger! Tap each object to measure it, then figure out which is longer!
The big lines on a ruler show centimetres. But there are also smaller lines between them — those are half centimetres and millimetres! Click the ruler to zoom in!
Before you measure, it's fun to estimate — that means make a smart guess!
Remy has a secret trick: he knows that his thumb is about 1 cm wide! So he uses his thumb to make a rough guess before measuring.
How to estimate:
1️⃣ Look at the object
2️⃣ Think: How many thumbs wide is it?
3️⃣ That's your estimate in cm!
4️⃣ Then measure to check!
Good estimates help you check if your measurement makes sense. If you measure a pencil and get "52 cm" — that's too big! Something went wrong!
Remy measures things every day! Let's see where measuring is used in real life. Tap each scene to learn more!
Remy is measuring things in his bedroom! Tap each object to measure it with the ruler! Can you read all the measurements correctly?
After measuring, we can compare lengths!
🔵 Longer = bigger number
🟠 Shorter = smaller number
🟢 Same = equal numbers
Example: A pencil is 8 cm. A crayon is 6 cm.
The pencil is longer because 8 > 6!
Top Tip: Line both objects up at the same starting point — then it's easy to see which sticks out further on the right!
Remy is at the zoo measuring the animals' features! Drag the ruler to measure each animal part and discover amazing facts!
Type the name above, then download or print your certificate!