Lesson Notes By Weeks and Term v4 - Basic 4

Lesson Video

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Performance objectives

• Identify and describe basic shapes like squares and rectangles.
• Measure the perimeter of simple shapes.
• Calculate the area of rectangles and squares.
• Apply this knowledge to solve real-life problems.

Lesson summary

Today, we are going to learn about "perimeter." Perimeter is a big word, but it has a very simple meaning: it is the total distance around the outside of a shape. Imagine you are walking around the edge of your school field, or a farmer putting a fence around a garden to keep goats away from the vegetables. The total length of that walk or that fence is the perimeter. Understanding perimeter is very useful for many jobs like carpentry, farming, and tailoring.

Lesson notes

Concept 1: What is a Polygon?

A polygon is any flat, closed shape that is made up of straight lines. Examples: Triangles (3 sides), Squares (4 sides), Rectangles (4 sides), Pentagons (5 sides). Non-examples: A circle (it has a curved line, not straight lines), a shape that is not closed. Concept 2: What is Perimeter?

Perimeter is the total distance around the outside of a polygon. To find the perimeter, we simply add the lengths of all the sides together. The word comes from two parts: 'peri' which means 'around' and 'meter' which means 'measure'. So, it's the 'measure around' a shape.

We use units of length to measure perimeter, like centimetres (cm), metres (m), or kilometres (km). Concept 3: Calculating the Perimeter of Irregular Polygons