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Types of Triangles KS2

Get straight to the point (!) with this ready-to-teach Types of Triangles KS2 lesson. The lesson begins by defining different types of triangle according to their special properties. The included slides and activities provide plenty of opportunities for children to identify and sort different triangles, and use a range of mathematical vocabulary to describe them, too!

 

This Types of Triangles KS2 Maths lesson includes:

  • a detailed lesson plan with differentiated activities
  • a slideshow for the teaching input
  • a range of printable resources for independent learning activities
  • a handy answer sheet to make marking and feedback a breeze!

This lesson is part of a Angles and Triangles Unit for Year 5.

Types of Triangles KS2 Lesson Pack

£2.99

Scroll through the pictures for a preview of the lesson's resources:

Types of triangle ks2 Example Slide
Types of Triangles KS2 Slide Example
Types of Triangles KS2 Slide Example 2
Types of Triangles KS2 Slide Example 3
Types of Triangles KS2 Work Example
Types of Triangles KS2 Work Example 1
Types of Triangles KS2 Work Example 2
Types of Triangles KS2 Answers Example
Types of Triangles KS2 Plan Example
Examples of an equilateral,

Classifying Types of Triangles KS2

What is a triangle?

A triangle is a 2-D polygon which has three sides.

What are the different types of triangles?

When classifying triangles by the length of their sides there are three main types: equilateral, isosceles and scalene.

Equilateral triangles

Examples of equilateral triangles

As the name suggests, the sides and angles of an equilateral triangle are all equal. This type of triangle could also be referred to as a regular triangle.

Isosceles triangles

Examples of isosceles triangles

An isosceles triangle has two equal sides and two equal angles.

Scalene triangles

Examples of scalene triangles

A scalene triangle has no equal angles or sides.

Right-angled triangles

Some triangles can be classified by the angles within them. A common example of this is a right-angled triangle. One of a right-angled triangle's angles is 90° (a right-angle). Right-angled triangles can also be classed as scalene or isosceles triangles depending on the length of the sides.

Examples of right-angled triangles

Other examples of classifying triangles by angles include:

Acute triangles: A triangle where all the angles are less than 90°.

Obtuse angles: A triangle where one of the angles is more than 90°.

When do children learn about types of triangles?

  • Year 4
    • compare and classify geometric shapes, including quadrilaterals and triangles, based on their properties and sizes
  • Year 6
    • compare and classify geometric shapes based on their properties and sizes and find unknown angles in any triangles, quadrilaterals, and regular polygons