Mathematics

Beginner

40 mins

Teacher/Student led

Learning Goals

Learning Outcomes

Lesson Files

+80 XP

What you need:
IWB/Projector/Large Screen

2D Shapes: Naming and Counting Sides and Corners

Learn to count the straight sides and corners of flat shapes, and use these features to name shapes you haven't seen before. Explore triangles, squares, rectangles and circles.

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1 Getting Started
2 Watch and Notice
3 Try It Together
4 Draw and Label in Your Copy
5 Class Challenge
6 What Did We Notice?
7 What's Next
Pupil practice

1 - Getting Started ~4 mins

Illustration for Getting Started Look at these four shapes: a square, a triangle, a rectangle and a circle. One of them is different from all the others. Which one would you put on its own, and what is it about that shape that makes it the odd one out?

👇 Mark your steps as done as you complete them.

+5 XP

2 - Watch and Notice ~9 mins

Watch as we go round each shape and count its sides and corners. Count along with me. What stays the same from one shape to the next, and what changes?

👇 Mark your steps as done as you complete them.

+10 XP

3 - Try It Together ~8 mins

Let's try this together. I'll show a shape on the board, and one of you will come up to tap and count its sides and its corners, then tell us its name. The rest of us will check the count together.

Count the sides and corners

+15 XP

4 - Draw and Label in Your Copy ~3 mins

COPYBOOK MOMENT

In your maths copy, draw a triangle, a square and a rectangle. Beside each shape, write how many sides and how many corners it has, like this: triangle — 3 sides, 3 corners.

+10 XP

5 - Class Challenge ~9 mins

Now let's work through some questions together. The board will show one question at a time — read just the question you can see, and we'll check each answer before the next one appears.

How many sides and corners?

+15 XP

6 - What Did We Notice? ~3 mins

MATHS TALK

How can counting the sides and corners help you name a shape you have never seen before?

+10 XP

7 - What's Next ~3 mins

Today you learned

How to count the straight sides and corners of a flat shape
That the number of sides matches the number of corners
That a circle has no straight sides and no corners — just one curved edge
How to name a shape from its parts

Coming up

Next we will take the same shapes and sort them into groups by their properties — by how many sides they have, by whether they have corners, and by whether all their sides are the same length.

+5 XP

Pupil practice

Module 7 · 2D and 3D Shapes and Angles Shape & Space

Lesson 77 · 2D Shapes: Naming and Counting Sides and Corners

Download Activity Book page (PDF)

End of lesson

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2D Shapes: Naming and Counting Sides and Corners

Teacher Class Feed

1 - Getting Started ~4 mins

2 - Watch and Notice ~9 mins

3 - Try It Together ~8 mins

Count the sides and corners

4 - Draw and Label in Your Copy ~3 mins

5 - Class Challenge ~9 mins

How many sides and corners?

6 - What Did We Notice? ~3 mins

7 - What's Next ~3 mins

Today you learned

Unlock the full learning experience

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