Skip to content
Oak National Academy
Oak National Academy
Teachers
Pupils
New
New
Year 1

Explore, discuss and identify shapes that are and are not triangles

I can say if a shape is a triangle or not and explain why.

Download all resources
Share activities with pupils
New
New
Year 1

Explore, discuss and identify shapes that are and are not triangles

I can say if a shape is a triangle or not and explain why.

Download all resources
Share activities with pupils

Lesson details

Key learning points

  1. Use everyday language to describe what different shapes look like.
  2. Identify shapes that are triangles because they have 3 straight sides and 3 vertices.
  3. A vertex is the corner of the shape where the sides meet.

Common misconception

Children may mistake some 'triangle-like' shapes as triangles.

Provide cut-outs of shapes to handle and explore. Make a list of properties a triangle must have and discuss them for each cut-out.

Keywords

  • Sides - The edges of a shape.

  • Vertices - The corners of a shape where two or more sides meet.

  • Triangle - A 2D shape with three straight sides and three vertices.

  • Straight - A line or surface with no curves.

Ensure children have plenty of opportunities to handle cut-outs of triangles and triangle-like shapes as well as looking at pictures so they can handle them and describe how the sides and vertices feel in their hands.
Teacher tip

Licence

This content is © Oak National Academy Limited (2024), licensed on Open Government Licence version 3.0 except where otherwise stated. See Oak's terms & conditions (Collection 2).

Video

Skip video

Loading...

Starter quiz

Download starter quiz

6 Questions

Q1.
Which shape is Alex describing?
An image in a quiz
A
Correct answer: B
C
Q2.
Which shape has 1 straight side and 1 curved line?
Correct answer: A
B
C
Q3.
How many vertices does this shape have?
An image in a quiz
2
3
Correct answer: 4
5
Q4.
Which line has been sorted correctly?
An image in a quiz
A
Correct answer: B
C
Q5.
Tick all the names that are 2D shapes.
Correct answer: circle
cube
Correct answer: triangle
Correct answer: rectangle
cone
Q6.
Look how these shapes have been sorted. Which shape has been placed in the wrong set?
An image in a quiz
A
B
Correct answer: C

Exit quiz

Download exit quiz

6 Questions

Q1.
Which shape has only 3 straight sides?
A
Correct answer: B
C
Q2.
Which shape has only 3 vertices?
Correct answer: A
B
C
Q3.
Find the shape that has only 3 vertices.
A
Correct answer: B
C
Q4.
Tick all the triangles.
A
Correct answer: B
C
Correct answer: D
Q5.
This shape is not a triangle because __________.
An image in a quiz
Correct answer: it has more than 3 sides.
it has curved lines.
it has no vertices.
Q6.
Which shape doesn't belong in this set?
An image in a quiz
Correct answer: A
B
C

Additional material

Download additional material
We're sorry, but preview is not currently available. Download to see additional material.