📏 Perimeter and Area
Class 4 Maths · Unit 9 of 12 · about 120 minutes
This unit introduces perimeter as the distance around a shape (found by adding side lengths) and area as the amount of space inside a shape (found by counting unit squares on a grid). Children will compare shapes with the same perimeter or area, and solve simple real-life problems involving fencing and tiling. This foundation supports later work with measurement and geometry.
What your child will learn
- Students will be able to find the perimeter of a polygon by adding the lengths of all its sides.
- Students will be able to find the area of a shape by counting the number of unit squares it covers on a grid.
- Students will be able to compare two shapes and state which has a larger perimeter or area, using counting or addition.
Lessons in this unit
- Perimeter: Distance Around: Understand perimeter as the total distance around a shape. Learn to find it by adding the lengths of all sides.
- Area: Counting Squares: Understand area as the amount of space inside a shape. Learn to find it by counting unit squares on a grid.
- Comparing Perimeter and Area: Compare shapes to see which has a larger perimeter or area, using counting and addition. Understand that shapes can have the same perimeter but different areas, and vice versa.
Key words
- perimeter
- The total distance around the outside of a shape.
- area
- The amount of space inside a shape.
- unit square
- A square with sides of length 1 unit, used to measure area.
- grid
- A pattern of squares that helps us count area.
- side
- One of the straight edges of a shape.
- length
- How long something is.
- width
- How wide something is.
Help your child at home
What to watch for
- Perimeter is the space inside the shape.
- Help: Perimeter is the distance around the outside. Walk around the shape to feel it.
- Area is the distance around the shape.
- Help: Area is the space inside. Imagine filling the shape with tiles.
- If two shapes have the same perimeter, they must have the same area.
- Help: Perimeter and area are different. A long thin rectangle and a square can have the same perimeter but different areas.
- Only add two sides (length and width) for a rectangle.
- Help: A rectangle has four sides. Add all four: length + width + length + width.
Try this at home
- Rectangle 6 cm by 4 cm: walk around and add each side, 6 + 4 + 6 + 4 = 20 cm
- Rectangle on a grid with squares counted
- Two rectangles with different dimensions, compare perimeter
- Square with side 5 cm: four equal sides, 5 + 5 + 5 + 5 = 20 cm
Quick questions to ask aloud
- What is the perimeter of a shape? (The distance around the outside / The space inside the shape / The length of one side / The number of squares inside)
Show answer
The distance around the outside. Perimeter is the total distance around the outside of a shape. You find it by adding all the side lengths. - What does area measure? (The space inside a shape / The distance around a shape / The length of a side / The weight of a shape)
Show answer
The space inside a shape. Area is the amount of space inside a shape. We measure it by counting unit squares. - Rectangle A is 2 cm by 6 cm. Rectangle B is 3 cm by 4 cm. Which has the larger perimeter? (Rectangle A / Rectangle B / They are the same / Cannot tell)
Show answer
Perimeter of A = 2 + 6 + 2 + 6 = 16 cm. Perimeter of B = 3 + 4 + 3 + 4 = 14 cm. So Rectangle A has the larger perimeter.
Frequently asked questions
What will my child learn in "Perimeter and Area" (Class 4 Maths)?
Your child will be able to: find the perimeter of a polygon by adding the lengths of all its sides.; find the area of a shape by counting the number of unit squares it covers on a grid.; compare two shapes and state which has a larger perimeter or area, using counting or addition..
How does MangoMindz teach "Perimeter and Area"?
In 3 short parts (Perimeter: Distance Around, Area: Counting Squares, Comparing Perimeter and Area). Each part has a picture-based lesson read aloud by Mango Teacher, a quick check, and a quiz built from common mistakes children make, with Mango, a study buddy, for questions.
How long does "Perimeter and Area" take?
About 120 minutes in total, spread over 3 parts of 15–25 minutes each.
How can I help my child with "Perimeter and Area" at home?
Work through a small example together, such as: Rectangle 6 cm by 4 cm: walk around and add each side, 6 + 4 + 6 + 4 = 20 cm; Rectangle on a grid with squares counted. Then ask a quick question aloud: What is the perimeter of a shape? (The distance around the outside / The space inside the shape / The length of one side / The number of squares inside)
What mistakes do children often make in "Perimeter and Area"?
Perimeter is the space inside the shape. Fix: Perimeter is the distance around the outside. Walk around the shape to feel it. Area is the distance around the shape. Fix: Area is the space inside. Imagine filling the shape with tiles. If two shapes have the same perimeter, they must have the same area. Fix: Perimeter and area are different. A long thin rectangle and a square can have the same perimeter but different areas.
Is "Perimeter and Area" free on MangoMindz?
Yes. Every lesson part and quiz in "Perimeter and Area" is free on MangoMindz, with no ads.