UNIVERSITY OF SOUTH AFRICA
College of Education — Department of Mathematics Education
⋄ ⋄ ⋄ ⋄ ⋄ ⋄ ⋄ ⋄ ⋄⋄
TMN3704: Teaching Mathemat-
ics in the Intermediate Phase
Assessment 3 — Year Module, 2026
⋄ ⋄ ⋄ ⋄ ⋄ ⋄ ⋄ ⋄ ⋄⋄
TMN3704
Module Code:
Teaching Mathematics in the Intermediate
Module Name:
Phase
Properties of 2D Shapes — Angles (Grade
Focus:
5)
03
Assignment Number:
638428
Unique Number:
08 July 2026
Due Date:
50
Total Marks:
Submitted in partial fulfilment of the requirements for TMN3704 — UNISA 2026
,UNISA | TMN3704 Assessment 3 — 2026
Contents
1 Activity 1: 2D Shapes — Definition and CAPS Context 4
1.1 1.1 Definition of 2D Shapes . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
1.2 1.2 Two Key Concepts Derived from the Definition . . . . . . . . . . . . 4
1.3 1.3 Properties of 2D Shapes in the CAPS Document . . . . . . . . . . . 5
1.3.1 1.3.1 Term(s) in Which the Topic Is Taught in Grade 5 . . . . . . 5
1.3.2 1.3.2 Time Allocated to Properties of 2D Shapes in Grade 5 . . 6
2 Activity 2: Lesson Planning — Aim, Objectives, and Prior Knowledge 7
2.1 2.1 Aim of the Lesson . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
2.2 2.2 Learning Objectives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
2.3 2.3 Prior Knowledge Required: Angles Smaller Than Right Angles . . 8
3 Activity 3: Lesson Introduction — Angles Greater Than Right Angles 9
3.1 3.1 Introduction Strategy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
4 Activity 4: Teaching Fractions Using the Fraction Wall 11
4.1 4.1 Two Key Concepts for Teaching Fractions Using the Fraction Wall 11
4.2 4.2 Two Suitable Learning Approaches . . . . . . . . . . . . . . . . . . . . 12
4.3 4.3 Assessment Questions for Each Key Concept and Skill . . . . . . . . 12
4.3.1 For Concept 1 (Part-Whole Relationship) via Cooperative Learn-
ing: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
4.3.2 For Concept 2 (Equivalent Fractions) via Problem-Based Learn-
ing: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
4.4 4.4 Analytical Rubric for Activity 4.3 . . . . . . . . . . . . . . . . . . . . . 13
5 Activity 5: Inquiry / Investigation — Properties of a Rectangle (Grade 6) 14
Page 2 of 18
,UNISA | TMN3704 Assessment 3 — 2026
5.1 5.1 Investigation: Exploring the Properties of a Rectangle . . . . . . . . 15
5.1.1 Important Idea 1: Opposite Sides Are Equal in Length . . . . . . 15
5.1.2 Important Idea 2: All Four Angles Are Right Angles . . . . . . . 15
5.1.3 Important Idea 3: Diagonals Are Equal in Length and Bisect Each
Other . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
5.1.4 Important Idea 4: Opposite Sides Are Parallel . . . . . . . . . . . 16
5.1.5 Important Idea 5: Lines of Symmetry . . . . . . . . . . . . . . . . . 17
Reference List 18
Page 3 of 18
,UNISA | TMN3704 Assessment 3 — 2026
Activity 1: 2D Shapes — Definition and CAPS Context
Two-dimensional shapes form the conceptual foundation of the Space and Shape content area
in the Intermediate Phase, and understanding their defining attributes is essential before any
classification, angle recognition, or geometric reasoning can occur (Department of Basic Edu-
cation [DBE], 2011).
1.1 Definition of 2D Shapes
A two-dimensional (2D) shape is a flat, closed figure that exists entirely within a single plane
and possesses only two measurable attributes: length and width. It has no depth or volume.
A 2D shape is bounded by straight or curved lines, and the space enclosed by those lines con-
stitutes its area. Examples found in the South African intermediate phase context include
triangles, squares, rectangles, circles, pentagons, and hexagons (DBE, 2011:21). According
to Siemon et al. (2013:264), 2D shapes are plane figures that can be drawn on a flat surface,
and their properties are described entirely in terms of their sides, vertices, angles, and lines
of symmetry. The CAPS document for Mathematics Grades 4–6 further situates 2D shapes
within the content area of Space and Shape, where learners are expected to recognise, visu-
alise, name, describe, sort, and compare these shapes according to their geometric properties
(DBE, 2011:21).
Key Distinction
A 2D shape occupies two dimensions only: length and width. Any figure that has
depth (a third dimension) is classified as a 3D object. A square drawn on paper is 2D;
a cube held in the hand is 3D. This distinction is fundamental at Grade 5 level and
underpins all subsequent geometric learning.
1.2 Two Key Concepts Derived from the Definition
Two concepts from the definition of 2D shapes are central to the lesson focus on angles: plane
and closed figure.
Concept 1: Plane (Flat Surface). The term “plane” refers to a perfectly flat, two-dimensional
surface that extends infinitely in all directions but has no thickness. A 2D shape exists en-
tirely within this plane, meaning all its points, sides, and angles lie on the same flat level.
This is significant in the classroom context because Grade 5 learners encounter angles within
Page 4 of 18
, UNISA | TMN3704 Assessment 3 — 2026
plane figures; the flatness of the surface is what allows angles to be measured, compared, and
classified (Siemon et al., 2013:265). When a learner holds a triangle cut from cardboard, the
two-dimensional nature of that shape means each interior angle exists at the meeting point of
two sides on a flat surface, making it observable and measurable.
Concept 2: Closed Figure. A closed figure is a shape whose boundary forms a complete,
unbroken path with no gaps or openings, where the starting and ending points of the bound-
ary coincide. This is essential because an angle in a 2D shape is formed specifically at the
vertex where two sides of a closed boundary meet. Without closure, there is no complete ver-
tex, and therefore no interior angle to identify or measure (DBE, 2011:21). In practical terms,
learners need to understand that an open line or an incomplete path does not constitute a 2D
shape and, consequently, cannot contain angles of the type studied under the Properties of
2D Shapes topic.
Table 1: Summary of Key Concepts in the Definition of 2D Shapes
Concept Meaning Relevance to Angles
Plane Flat, two-dimensional surface Angles within 2D shapes lie on a
with no depth flat surface and can be observed
and measured
Closed Figure A boundary with no gaps where Angles are formed at vertices
the start and end points meet where two sides of a closed
boundary meet
1.3 Properties of 2D Shapes in the CAPS Document
1.3.1 Term(s) in Which the Topic Is Taught in Grade 5
According to the CAPS Mathematics document for Grades 4–6, the topic of Properties of 2D
Shapes is taught in Grade 5 during Term 2 and Term 3. In Term 2, the focus is on recog-
nising, describing, and comparing 2D shapes and their properties, including lines and angles.
In Term 3, learners extend this understanding by focusing more specifically on symmetry, an-
gle types, and properties such as parallel and perpendicular lines within 2D shapes. This dis-
tribution across two terms allows for a spiral curriculum approach, where initial exposure in
Term 2 is consolidated and deepened in Term 3 (DBE, 2011:22).
Page 5 of 18
College of Education — Department of Mathematics Education
⋄ ⋄ ⋄ ⋄ ⋄ ⋄ ⋄ ⋄ ⋄⋄
TMN3704: Teaching Mathemat-
ics in the Intermediate Phase
Assessment 3 — Year Module, 2026
⋄ ⋄ ⋄ ⋄ ⋄ ⋄ ⋄ ⋄ ⋄⋄
TMN3704
Module Code:
Teaching Mathematics in the Intermediate
Module Name:
Phase
Properties of 2D Shapes — Angles (Grade
Focus:
5)
03
Assignment Number:
638428
Unique Number:
08 July 2026
Due Date:
50
Total Marks:
Submitted in partial fulfilment of the requirements for TMN3704 — UNISA 2026
,UNISA | TMN3704 Assessment 3 — 2026
Contents
1 Activity 1: 2D Shapes — Definition and CAPS Context 4
1.1 1.1 Definition of 2D Shapes . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
1.2 1.2 Two Key Concepts Derived from the Definition . . . . . . . . . . . . 4
1.3 1.3 Properties of 2D Shapes in the CAPS Document . . . . . . . . . . . 5
1.3.1 1.3.1 Term(s) in Which the Topic Is Taught in Grade 5 . . . . . . 5
1.3.2 1.3.2 Time Allocated to Properties of 2D Shapes in Grade 5 . . 6
2 Activity 2: Lesson Planning — Aim, Objectives, and Prior Knowledge 7
2.1 2.1 Aim of the Lesson . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
2.2 2.2 Learning Objectives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
2.3 2.3 Prior Knowledge Required: Angles Smaller Than Right Angles . . 8
3 Activity 3: Lesson Introduction — Angles Greater Than Right Angles 9
3.1 3.1 Introduction Strategy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
4 Activity 4: Teaching Fractions Using the Fraction Wall 11
4.1 4.1 Two Key Concepts for Teaching Fractions Using the Fraction Wall 11
4.2 4.2 Two Suitable Learning Approaches . . . . . . . . . . . . . . . . . . . . 12
4.3 4.3 Assessment Questions for Each Key Concept and Skill . . . . . . . . 12
4.3.1 For Concept 1 (Part-Whole Relationship) via Cooperative Learn-
ing: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
4.3.2 For Concept 2 (Equivalent Fractions) via Problem-Based Learn-
ing: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
4.4 4.4 Analytical Rubric for Activity 4.3 . . . . . . . . . . . . . . . . . . . . . 13
5 Activity 5: Inquiry / Investigation — Properties of a Rectangle (Grade 6) 14
Page 2 of 18
,UNISA | TMN3704 Assessment 3 — 2026
5.1 5.1 Investigation: Exploring the Properties of a Rectangle . . . . . . . . 15
5.1.1 Important Idea 1: Opposite Sides Are Equal in Length . . . . . . 15
5.1.2 Important Idea 2: All Four Angles Are Right Angles . . . . . . . 15
5.1.3 Important Idea 3: Diagonals Are Equal in Length and Bisect Each
Other . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
5.1.4 Important Idea 4: Opposite Sides Are Parallel . . . . . . . . . . . 16
5.1.5 Important Idea 5: Lines of Symmetry . . . . . . . . . . . . . . . . . 17
Reference List 18
Page 3 of 18
,UNISA | TMN3704 Assessment 3 — 2026
Activity 1: 2D Shapes — Definition and CAPS Context
Two-dimensional shapes form the conceptual foundation of the Space and Shape content area
in the Intermediate Phase, and understanding their defining attributes is essential before any
classification, angle recognition, or geometric reasoning can occur (Department of Basic Edu-
cation [DBE], 2011).
1.1 Definition of 2D Shapes
A two-dimensional (2D) shape is a flat, closed figure that exists entirely within a single plane
and possesses only two measurable attributes: length and width. It has no depth or volume.
A 2D shape is bounded by straight or curved lines, and the space enclosed by those lines con-
stitutes its area. Examples found in the South African intermediate phase context include
triangles, squares, rectangles, circles, pentagons, and hexagons (DBE, 2011:21). According
to Siemon et al. (2013:264), 2D shapes are plane figures that can be drawn on a flat surface,
and their properties are described entirely in terms of their sides, vertices, angles, and lines
of symmetry. The CAPS document for Mathematics Grades 4–6 further situates 2D shapes
within the content area of Space and Shape, where learners are expected to recognise, visu-
alise, name, describe, sort, and compare these shapes according to their geometric properties
(DBE, 2011:21).
Key Distinction
A 2D shape occupies two dimensions only: length and width. Any figure that has
depth (a third dimension) is classified as a 3D object. A square drawn on paper is 2D;
a cube held in the hand is 3D. This distinction is fundamental at Grade 5 level and
underpins all subsequent geometric learning.
1.2 Two Key Concepts Derived from the Definition
Two concepts from the definition of 2D shapes are central to the lesson focus on angles: plane
and closed figure.
Concept 1: Plane (Flat Surface). The term “plane” refers to a perfectly flat, two-dimensional
surface that extends infinitely in all directions but has no thickness. A 2D shape exists en-
tirely within this plane, meaning all its points, sides, and angles lie on the same flat level.
This is significant in the classroom context because Grade 5 learners encounter angles within
Page 4 of 18
, UNISA | TMN3704 Assessment 3 — 2026
plane figures; the flatness of the surface is what allows angles to be measured, compared, and
classified (Siemon et al., 2013:265). When a learner holds a triangle cut from cardboard, the
two-dimensional nature of that shape means each interior angle exists at the meeting point of
two sides on a flat surface, making it observable and measurable.
Concept 2: Closed Figure. A closed figure is a shape whose boundary forms a complete,
unbroken path with no gaps or openings, where the starting and ending points of the bound-
ary coincide. This is essential because an angle in a 2D shape is formed specifically at the
vertex where two sides of a closed boundary meet. Without closure, there is no complete ver-
tex, and therefore no interior angle to identify or measure (DBE, 2011:21). In practical terms,
learners need to understand that an open line or an incomplete path does not constitute a 2D
shape and, consequently, cannot contain angles of the type studied under the Properties of
2D Shapes topic.
Table 1: Summary of Key Concepts in the Definition of 2D Shapes
Concept Meaning Relevance to Angles
Plane Flat, two-dimensional surface Angles within 2D shapes lie on a
with no depth flat surface and can be observed
and measured
Closed Figure A boundary with no gaps where Angles are formed at vertices
the start and end points meet where two sides of a closed
boundary meet
1.3 Properties of 2D Shapes in the CAPS Document
1.3.1 Term(s) in Which the Topic Is Taught in Grade 5
According to the CAPS Mathematics document for Grades 4–6, the topic of Properties of 2D
Shapes is taught in Grade 5 during Term 2 and Term 3. In Term 2, the focus is on recog-
nising, describing, and comparing 2D shapes and their properties, including lines and angles.
In Term 3, learners extend this understanding by focusing more specifically on symmetry, an-
gle types, and properties such as parallel and perpendicular lines within 2D shapes. This dis-
tribution across two terms allows for a spiral curriculum approach, where initial exposure in
Term 2 is consolidated and deepened in Term 3 (DBE, 2011:22).
Page 5 of 18
