Short Blocks

Maths Year 4 Spring Shape (B)

Each unit has everything you need to teach a set of related skills and concepts.

Line of symmetry: identify and construct (suggested as 2 days)

Planning and Activities

Day 1 Teaching
Display a pattern drawn on one side of a line of symmetry (see resources). Discuss the concept of ‘line of symmetry’ and begin to complete each pattern. Provide copies for children who complete each symmetrical pattern. Children create their own symmetrical patterns, colouring just 12 squares lines of symmetry.
Group Activities
-- Create symmetrical patterns across one or two lines of symmetry.

Day 2 Teaching
Draw an irregular but symmetrical hexagon. Ask children to say whether it has a line of symmetry. Then draw half of an irregular but symmetrical octagon. Children need to draw the other half. Discuss shapes with two lines of symmetry and draw one, identifying the two lines. Model how to use a mirror to check for symmetry, perhaps using the Symmetry ITP.
Group Activities
Use the in-depth problem-solving investigation ‘Tremendous Tiles’ as today’s group activity.
Or, use these activities:
-- Identify the lines of symmetry on 2-D shapes; draw shapes with a given number of lines of symmetry.
-- Identify whether shapes are symmetrical. Draw the lines of symmetry on 2-D shapes.

You Will Need

  • ‘Symmetrical patterns’ sheets 1 and 2 (see resources)
  • Squared paper
  • ITP: Symmetry
  • ‘Shapes for sorting’ sheet (see resources)
  • Mirrors, rulers and a set of 2D shapes (regular, irregular, symmetrical, not symmetrical)

Mental/Oral Maths Starters

Suggested for Day 1
Draw irregular polygons (simmering skills)

Suggested for Day 2
Compare pairs of numbers with 2 decimal places (simmering skills)

Or

Suggested for Day 2
Count on or back in steps of 50 and 100 (simmering skills)

Mastery: Reasoning and Problem-Solving

  • Shade 4 more spaces on this grid (see download) to create a pattern with two lines of symmetry.
  • Draw a shape with exactly four lines of symmetry. It does not need to be a polygon.
  • By shading just one ‘cell’ on a 3 by 3 square grid, how many different symmetrical patterns can you make? Be careful not to count reflections or rotations of patterns already made…
    How many different patterns can you make if you are allowed to shade 2, 3, 4 or 5 cells?
    Can you make a prediction about how the number of patterns with 6 cells shaded will relate to the number with 3 cells shaded?

In-depth Investigation: Tremendous Tiles
Children explore creating patterns of tiles with three asymmetrical blocks. They look for and identify lines of symmetry, creating patterns with at least two lines of reflective symmetry.

Extra Support

Colouring Triangles
Make symmetrical patterns by colouring the set of triangles. Colouring Triangles from nrich.maths.org.