Chapter 3 - Shapes and Solids

Shapes and Solids

Primary 3 Math

Geometry

Term 2

2020

Learning Objective: Students will be able to,

• identify and describe shapes and solids

• describe shapes and solids using their properties

• identify line of symmetry in the environment

• draw shapes using spotty paper

• draw and complete shapes with reflective symmetry

• recognize nets that will make a cube

Two-dimensional Shapes (2D Shapes)

Open Ended

What are the properties of 2D shapes?

Properties of 2D Shapes;

• Side

• Vertex (plural: vertices)

• Angle (Right angle)

Open Ended

Name this shape and describe the number of sides, vertices and right angles.

This is a rectangle.

It has 4 sides, 4 vertices and 4 right angles.

Open Ended

Name this shape and describe the number of sides, vertices and right angles.

This is a hexagon.

It has 6 sides, 6 vertices and no right angles.

Open Ended

Name this shape.

How many sides and vertices does it have?

This is an irregular hexagon.

It has 6 sides and 6 vertices.

Poll

Can you find any right angles in this shape?

• Yes

• No

Multiple Choice

If yes, how many right angles are there?

• 0

• 1

• 2

• 3

This is a right triangle.

It has 1 right angle.

Open Ended

Name this shape.

How many right angles are there in this shape?

This is a trapezoid.

It has no right angles.

Multiple Choice

What is polygon?

• Polygon is all 2D shapes.

• Polygon is 2D shapes with all straight sides.

• Polygon is 2D shapes with all curved sides.

Polygon

A flat shape (two-dimensional) with straight sides.

Open Ended

Which shapes below is not a polygon?

Semi circle is not a polygon because it has 1 curved side.

Open Ended

We have learned about classifying/sorting out the 2D shapes.

What is the correct name/label for this set of shapes?

These shapes are quadrilateral. They have 4 sides and 4 vertices.

Three-dimensional Shape (3D Shapes/ Solids)

Open Ended

What are the properties of 3D shapes?

Properties of 2D Shapes;

• Face

• Vertex (plural: vertices)

• Edge

Open Ended

Name this solid and describe the number of face, edge and vertices.

This is a Sphere.

It has 1 curved face (surface), no edge and no vertex.

Open Ended

Name this shape and describe the number of face, edge and vertices.

This is a triangular pyramid/ tetrahedron.

It has 4 faces, 4 vertices and 6 edges.

Open Ended

Name this shape and describe the number of face, edge and vertices.

This is a pentagonal prism.

It has 7 faces, 15 edges and 10 vertices.

Multiple Choice

What is this shape called?

• Cylinder

• Rectangular Prism

• Sphere

Open Ended

What solid does this object look like?

Open Ended

How many faces, vertices and edges does this object have?

This object looks like a cuboid/ rectangular prism.

It has 6 faces, 8 vertices and 12 edges.

Open Ended

What solid does this object look like?

Open Ended

How many faces, vertices and edges does this object have?

This object looks like a cone.

It has 2 faces, 1 edge and 1 vertex.

Nets

Net is a figure which can be folded to form a solid.

Here is the nets of cube

The number of parts in the cube is the same as the number of faces on the cube.

Multiple Select

Choose all correct nets of a cube below:

Symmetry

When two or more parts are identical/same after a flip, slide or turn.

Multiple Choice

Which shape below does not have a line of symmetry?

This is an equilateral triangle (same sides).

It has 3 line of symmetries.

This is an irregular hexagon.

It has no line of symmetry.

This is a trapezoid.

It has 1 line of symmetry.

Multiple Choice

Which one is the correct pattern to complete the pattern below it is identical?

Fill in the Blanks

It has 1 line of symmetry.

Fill in the Blanks

It has 1 line of symmetry.

Fill in the Blanks

It has 2 line of symmetry.