Addition and Subtraction Using an Open Number Line
Give students a powerful mental maths strategy — addition and subtraction on an open number line made accessible and clear.
The open number line is one of the most versatile and effective strategies for teaching addition and subtraction, and this resource makes it approachable for every learner. Students learn to use an open number line to solve problems by jumping forward and backward in meaningful chunks, building flexible thinking and deep number sense along the way.
Whether you're introducing the strategy or providing consolidation practice, this resource gives students a structured pathway from concrete to abstract thinking.
Why teachers love it:
- Strategy-based learning — students develop flexible mental maths strategies rather than relying on rote procedures
- Visual scaffold — the open number line makes abstract operations visible and manageable
- Differentiation-friendly — accessible for students at a range of levels within the same activity
- Curriculum-aligned — supports Australian Curriculum Number and Algebra outcomes
Perfect for:
- Years 2–4 addition and subtraction units
- Mental maths strategy instruction
- Guided maths and small group teaching
- Building number sense and flexible thinking
- Introducing or consolidating the open number line strategy
What's included:
A printable PDF resource teaching and practising addition and subtraction using the open number line strategy, with structured examples and practice problems.
Jump to it — the open number line strategy is a game-changer for mental maths!
Teaching place value?
Our place value teaching guide has ten strategies and hands-on activities to use alongside this resource.
SPECIFICATIONS
Format: PDF, set up for A4 paper. Exactly what's inside is listed above.
Editing: This download is not editable. The PDF is flattened to protect the design and the artists' work we license.
Printing: Open the file in a PDF reader and choose 'Fit to page' or 'Actual size'. Do a test page on plain paper first — card, colour and black-and-white all print well.
Licence: One classroom, one teacher. Please don't share, resell or post the file online; buy an extra licence for each colleague who wants their own copy.
TECHNICAL SUPPORT
You'll need a PDF reader on your device — the free Adobe Acrobat Reader is the most reliable. Double-click the downloaded file to open it.
If a page shows on screen but won't print properly, open it in Acrobat Reader, choose Print → Advanced → tick 'Print as image'.
Stuck? Contact us and we'll sort it out.
OUR HAPPINESS GUARANTEE
We want you to love every Mrs Edgar resource. If something isn't right, contact us within 30 days and we'll make it right. Because this is a digital file we can't refund a download that has already been opened, but we will always help you get it working. See our Returns Policy.
FAQS
Where is my download?
Check your inbox (and junk folder) for the email from Mrs Edgar with your link. You can also log in to your account at mrsedgar.com.au and download it from your order.
It came as a ZIP file — how do I open it?
On a Mac, double-click it. On Windows, right-click and choose 'Extract All'. Your PDFs will be inside.
Can I print in colour or black and white?
Yes. Our resources are designed to work both ways; black-and-white versions look great on coloured card.
The download won't start on my school computer.
Some school networks block downloads. Try again at home, or right-click the link and choose 'Save link as'.
