Number lines were not used for teaching addition and subtraction when I was at school, but when my kids started infant school we were introduced to these as a simple tool to help them understand these concepts. With my oldest, he has always been so quick with mental calculations that I admit I never saw the benefit in the number line and hardly used it. My younger boys (age 4 and 6, in Reception and year 1) changed my views on it though, as they like to use their number lines often and I can see that it does help them – making the concepts of addition and subtraction so simple and clear.
We decided to make our own number line using LEGO Duplo to make using a number line more tactile and fun.

What is a number line?
If you didn’t learn to use number lines in school either, they may be new to you too. A number line is simply a line of numbers, typically from 1-10 or 1-20, that allows children to count along forwards or backwards as a visual way of adding up or taking away.
For example, if you want to do 4 plus 3, you’ll go to 4 on the number line then count on three spaces, and see that you’ve landed on the 7 – so 4+3=7
For subtraction it’s the same idea but backwards, so for 10-2 you’ll start on 10 and count back two spaces to land on the 8.

LEGO DUPLO number line
So back to our LEGO DUPLO number line. To make this you will need:
- One or two base plates, depending on size
- Bricks totalling either 10 or 20 spaces. We used five 4×2 bricks, which is ideal since it makes 20 spaces
- Sharpie pen
- LEGO DUPLO figure
All you’ll need to do is write the numbers on the side of the bricks using a sharpie, and stick them down in order onto the base plates. This can be set up in under 5 minutes. The sharpie pen is permanent, so if you want to be able to wash or wipe it off later, try substituting for a dry wipe pen.

Now that your LEGO DUPLO number line is set up, your child can easily play and learn with it practising simple sums. I left ours out on the table for the kids to discover and they recognised it as a number line straight away and got into challenging each other with some simple addition and subtractions.

They can use this independently and this hands on practice helps to solidify the concept of addition and subtraction for the younger ones – with the added fun of LEGO!

More LEGO learning
Earlier this week, we made a LEGO days of the week activity for learning languages
For more LEGO learning ideas suited for KS1 (early elementary) check out these ideas shared this week by the rest of the Early Elementary blogging team. I would love to leave a question here. Are mega bloks the same as duplo? Let us know your thoughts in the comments. For my daughter I always chose mega bloks because I found that it worked better for her little hands and she had them from a very young age. But I may start considering duplos now that she is a little older. Let us know!

LEGO Classification – Printable Diagrams from Life Over C’s
LEGO number line for Addition and Subtraction from In The Playroom
Hands-On Synonym Blocks Matching Game from Raising Little Superhereos
Spelling With LEGOS! from Preschool Powol Packets
LEGO Boat Engineering Challenge from Handmade Kids Art
Using LEGO to find Syllables from Rainy Day Mum
Area and Perimeter with Lego Duplos from School Time Snippets
Plural Nouns with LEGO from Still Playing School
Combinations of Ten Using Lego Figures from Lemon Lime Adventures
How to do an Lego Engineering Project for Kindergarten, First, or Second Grade from Thriving STEM
Estimating and Probability with LEGO from Planet Smarty Pants
Lego Bar Graphs for First Grade from Look We’re Learning
LEGO Irregular Verb Matching Activity for Second Grade from Sugar Aunts
Exploring Symmetry with a Lego Firefly from Crafty Kids at Home
Pick Two: A Fun LEGO Math Game from Creative Family Fun
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Anna Marikar, mum of four and seasoned blogger, has spent over a decade sharing her parenting journey and passion for kid-friendly crafts and free printables.
Her easy-to-follow craft ideas and practical parenting advice have transformed In The Playroom into a cherished resource for parents.
what a great idea, and way to make it fun with the lego!
Such an awesome way to learn the number line!
such a cute idea
Great idea to help choldren interact and learn
Such a wonderful way to use LEGOs!
Great idea! It’s a great hands-on way to illustrate numbers – and of course…Legos! 😉
Emma recently posted…Googly Eye Monster Valentines
We love using Legos to work on math. This is a great way to help kids visualize the number line.
Love this idea, would certainly help me get my son more interested and I really think visuals help. Thanks for this. Some really great ideas on your page!
Hey! This is a fun activity. Thanks for sharing it with me. I have 2 young boys and they will love certainly enjoy this. I came across a game last night https://www.youtube.com/watch?v=xjLtpkjDVis which my children really enjoyed.
AYE! This was very cool and exciting. Thanks for sharing it with us. My kid’s love practicing math and they will enjoy this activity as well, I am sure. I came across another math game https://www.youtube.com/watch?v=xjLtpkjDVis which they really enjoyed.