Year 5/6 Bulletin MATHS
Learning Intention
To calculate area and perimeter, using division to solve for missing sides.
Learning Experience Overview
This week in mathematics, students investigated area and perimeter and began using division to find missing side lengths. Through discussion, hands-on problem solving, and reflection, students explored how different measurements describe shapes in different ways. The lesson followed our Whole–Small–Whole instructional model, allowing students to first build understanding together, then practise independently, and finally reflect on their learning.
FLUENCY
We began the lesson with our fluency practice, focusing on fact families and the relationship between multiplication and division.
Students explored how numbers can form connected groups of equations. For example:
8 × 5 = 40
5 × 8 = 40
40 ÷ 5 = 8
40 ÷ 8 = 5
These four equations belong to the same fact family because they all use the same numbers and show the connection between multiplication and division.
Students discussed how division helps us work backwards from multiplication, which became an important idea later in the lesson. Building this fluency helps students develop number confidence and prepares them to solve more complex problems.
WHOLE – Building Understanding Together
We started by revisiting two important measurement ideas: area and perimeter.
Students shared what they already knew:
- Perimeter is the distance around a shape.
- Area is the space inside a shape.
Together we looked at a rectangle and discussed how we could calculate both measurements. Students quickly remembered that perimeter means adding all the sides, while area means multiplying the length and width.
But then we added a twist.
What if we know the area, but one side is missing?
Students explored how division can help us find the unknown side. By thinking about how multiplication works, students realised that division can help us work backwards and solve the problem.
There were lots of great “aha” moments as students began connecting multiplication and division in a practical way.
SMALL – Students Exploring the Maths
Once students were confident with the idea, they worked through a range of challenges.
They calculated the area and perimeter of different rectangles and squares, checking their answers and discussing strategies with their peers.
Some students worked with simpler shapes to build confidence, while others challenged themselves with larger numbers and more complex comparisons.
Students were also asked to solve problems where one side of a shape was missing. Using the area and one known side length, they used division to determine the missing measurement.
Many students enjoyed the challenge of working out the unknown sides and explaining their thinking to classmates.
For students ready to extend their thinking even further, we explored questions such as:
- If two shapes have the same perimeter, can they have different areas?
- Can a shape with a larger perimeter have a smaller area?
These types of questions encouraged students to think more deeply about how shapes and measurements work.
WHOLE – Reflecting on Our Learning
At the end of the lesson, we came back together as a class to share the strategies students used.
Students talked about how they:
- identified the known measurements first
- used multiplication to calculate area
- used division to find missing side lengths
- checked their answers by working backwards
These conversations help students build confidence and show that in mathematics there are often multiple ways to approach a problem.
How Families Can Support Learning at Home
You can easily continue this learning with your child at home.
1. Measure everyday objects. Ask your child to measure things around the house such as books, tables, or placemats.
- What is the perimeter?
- What is the area?
2. Try a “missing side” challenge. For example:“If the area of a rectangle is 36 cm² and one side is 6 cm, what is the other side?”
3. Talk about shapes in the real world. Look at rectangles and squares in your home, garden, or local playground and ask your child how they might calculate the area or perimeter.
4. Ask them to explain their thinking. When children explain how they solved a problem, it strengthens their understanding.
Looking Ahead
Students showed excellent thinking and curiosity throughout this lesson. They are continuing to develop strong skills in measurement, multiplication, division, and problem solving, which will support them as we explore more complex shapes and real-world maths problems in future lessons.
We love seeing students become confident mathematicians who are willing to ask questions, try strategies, and explain their thinking.
Allira, Gemma and Gracie
allira.zeneli@education.vic.gov.au