Geometric Reasoning · B5 Mathematics

Lesson notes

Learning Objectives

Indicator: B5.3.4.2.2 - Identify images of a single transformation (i.e. reflection) of a 2D shapes in a plane

By the end of the lesson, learners can:

State that a reflection is a flip of a shape across a mirror line, and identify the object and its image in a given diagram
Study a set of 2D shapes placed around a mirror line and correctly identify which shape is the image of another shape
Match an object shape to its correct image among several options when given a specific mirror line (e.g., vertical, horizontal, or diagonal)
Justify their identification by checking that each point on the image is the same perpendicular distance from the mirror line as the corresponding point on the object
Apply the language of reflection (object, image, mirror line, x = 0, y = x) when describing which shape reflects onto which

Sign in with your phone number to read the full note and download the GES plan - free.

Sign in with phone number

Curriculum details

Strand: Geometry and Measurement (Strand 3)
Sub-strand: Geometric Reasoning (3.4)
Content standard: B5.3.4.2 - Perform a single transformation (i.e. reflection) on a 2D shape
Indicator: B5.3.4.2.2 - Identify images of a single transformation (i.e. reflection) of a 2D shapes in a plane
Suggested placement: Term 3, Week 8 (Week 32 of the year)
Our suggestion, laid out in curriculum order across three terms of twelve weeks. NaCCA does not fix the week, so follow your school's scheme of learning.
Source document note: The official curriculum document has a fault in this entry, so the curriculum text above is transcribed exactly as printed:

exemplars - p.106
Curriculum reference: Mathematics Curriculum for Primary Schools (Basic 4-6), 2019, p. 106
Transcribed from the official NaCCA publication. Check this page against the source.

Exemplars (from the NaCCA curriculum)

E.g. 1. Ask learners to identify images of reflections of given 2D shapes in a given plane. Ask learners to study the shapes and the mirror line and state which are objects and their images in the given four mirror lines. Shape E is the image of Shape B in mirror line 2 or the line x = 0 ; shape A is a reflection of shape E in the line y = x .

Nearly square colour mathematical teaching visual is organised as a table with horizontal divisions, vertical... — A nearly square colour mathematical teaching visual is organised as a table with horizontal divisions, vertical divisions, coloured regions. Visible labels, values, and notation include: line 2; C; line 3; line 1; *line 4.

 There is no indicator B5.3.4.2.1: content standard B5.3.4.2 has this single indicator, numbered .2.