Mathematics

Intermediate

50 mins

Teacher/Student led

Learning Goals

Learning Outcomes

Lesson Files

+80 XP

What you need:
IWB/Projector/Large Screen

Completing Symmetrical Patterns Across a Mirror Line

Complete symmetrical patterns by counting squares from a mirror line and placing reflected squares the same distance away on the opposite side.

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1 Getting Started
2 Watch and Notice
3 Try It Together
4 Build the Mirror 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 Here is half a butterfly. A straight mirror line runs down the middle of its body, and one wing is missing a coloured spot.

Look closely: the spot on the wing we can see sits a few squares out from the line. Where must the missing spot go on the other wing so the butterfly matches itself perfectly?

👇 Mark your steps as done as you complete them.

+5 XP

2 - Watch and Notice ~7 mins

Look at each example of a shape reflected across the mirror line. Notice how far each square sits from the line, and where its mirror square is. Some are trickier than they look.

👇 Mark your steps as done as you complete them.

+10 XP

3 - Try It Together ~9 mins

Today we work through this together: a few squares are coloured on one side of the mirror line, and we complete the other side so the pattern is symmetrical.

Key point

For each square we count how far it sits from the line, then place its mirror exactly the same number of squares away on the opposite side. Take your turn at the board and the class will agree or correct.

Complete the pattern across the line

+15 XP

4 - Build the Mirror in Your Copy ~3 mins

COPYBOOK MOMENT

Illustration for Build the Mirror in Your Copy In your maths copy on squared paper, draw a straight vertical mirror line down the middle of the page.

Colour three squares on the left of the line. Then shade their mirror squares on the right so the whole pattern is symmetrical. Count carefully each time: the same number of squares from the line, on the opposite side.

+10 XP

5 - Class Challenge ~11 mins

Today we work through these patterns together, each one a little trickier than the last: a four-square pattern, then a six-square pattern, then a pattern with a square sitting right on the mirror line.

Tip

Take your turn at the board, complete the pattern, then we check it before moving on.

Complete the symmetrical pattern

+15 XP

Pupil practice

Module 8 · Symmetry, Location and Transformation Shape & Space

Lesson 92 · Completing Symmetrical Patterns Across a Mirror Line

Download Activity Book page (PDF)

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