Lesson 4: Rotation & Reflection Rules
Learning Intention
I can perform reflections across a mirror line and rotations around a centre point.
Success Criteria
- I can reflect a shape across a vertical or horizontal line (equidistant).
- I can rotate a shape 90° or 180° around a specific point.
- I can describe the difference between a reflection and a rotation.
Lesson Sequence
1. Visual Hook (10 mins)
Show two images: One reflected in water (Reflection) and a pinwheel (Rotation).
Which one is which? How do you know?
2. Explicit Teaching: Reflection (15 mins)
Key Concept: Every point on the image is the same distance from the mirror line as the original.
Demo: Verify with a ruler. "A is 2 squares from the line, so A' must be 2 squares on the other side."
3. Explicit Teaching: Rotation (15 mins)
Key Concept: You need a Centre of Rotation. Use tracing paper.
1. Trace the Shape.
2. Put pencil on the Centre Point.
3. Turn the paper 90° (Quarter Turn). Trace the new position.
4. The Whāriki Block Challenge (20 mins)
Context: Whāriki (woven mats) often use rotational symmetry to create blocks.
Task: Start with one triangle motif in the top-left corner of a 2x2 grid.
- Level 1: Reflect it right, then reflect bottom.
- Level 2: Rotate it 90° clockwise three times to fill the grid.
- Level 3: Create a complex block using a mix of both.