🌟 Overview
This page provides engaging worksheets, hands-on activities, and video lessons to help students explore how addition and subtraction work together, how numbers can be split into parts, and how missing values can be found in simple number sentences.
Students build confidence by using part-part-whole diagrams, bar models, number facts, and inverse thinking to solve problems in flexible and visual ways.
📚 Lessons in This Unit
Includes engaging videos and worksheets for. Please click on the link to access the worksheets and videos for each subtopic:
🚀 Learning Path (Recommended Order)
| Step | 🔗 Lesson | 💡 What You Learn |
|---|---|---|
| 1️⃣ | 🔢Partitioning Numbers, Part-Part-Whole and Bar Models | Practise partitioning numbers and learn reading bar models |
| 2️⃣ | ✏️Inverse Operations in Year 3: Finding Unknown Numbers | Use fact families to find unknown numbers in equations and check answers by working backwards. |
| 3️⃣ | 🧩 Inverse Operations: Connecting Addition and Subtraction | Deepen their understanding of inverse operations by connecting mental addition and subtraction |
📚 Curriculum Reference
This topic and its accompanying materials are aligned with the Australian Curriculum: Mathematics (Version 9.0).
Code: AC9M3A01
Students learn to:
- 🧠 understand that addition and subtraction are connected as opposite operations
- ➕ use number facts to help solve subtraction problems
- 🧩 partition numbers into parts using visual models
- ❓ find unknown values in number sentences
- 🔍 record related addition and subtraction facts for the same numbers
🔗 Related Learning Areas
These topics work well alongside AC9M3A01:
Place Value (AC9M3N01)
Fractions (AC9M3N02)
Addition & Subtraction (AC9M3N03)
Multiplication & Division (AC9M3N04)
Estimation (AC9M3N05)
Mathematical Modelling (AC9M3N06)
📝 Helpful Tips
These activities are designed to strengthen number understanding and flexible thinking:
- 🔍 Use the whole and the parts – Ask: “What is the total? What parts do I know?”
- 🧩 Draw it out – Part-part-whole diagrams and bar models make number ideas easier to see
- 🔄 Think backwards – Use addition to help solve subtraction, and subtraction to check addition
- ➕ Record fact families – The same three numbers can make related addition and subtraction facts
- ❓ Look for the missing value – Decide whether the missing number is a part or the whole
- 💬 Explain the strategy – Students should say how they solved it, not just give the answer
- ⚡ Use known facts first – Start with simple facts and use them to solve trickier problems