Lesson Notes By Weeks and Term - Primary 4

Week 8

SUBJECT: MATHEMATICS

CLASS: PRIMARY 4

TERM: 3RD TERM

TOPIC: Shapes

SUBTOPIC:�� 3 dimensional shapes

BEHAVIOURAL OBJECTIVES: At the end of the lesson, pupils should be able to:

1. Distinguish between open and close shapes
2. State the properties of close shapes
3. Appreciate the presence and use 3 dimensional shapes in Homes.
4. Identify right angle,acute and obtuse andle in a plane shape.
5. Distinguish between horizontal and vertical.

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CONTENT

Cube

A cube has 8 vertices

A cube has 12 equal edges

A cube has 6 equal faces

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Cuboid

A cuboid has 8 vertices

A cuboid has 12 unequal edges

A cuboid has 6 unequal faces

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Cylinder

A cylinder has one curved face

It has two flat faces

It has no vertex

Sphere

A sphere has one curved face only.

Curved face

It has no edge and no vertex.

Cone

A cone has 1 vertex

A cone has 1 curved face

A cone has 1 flat face (i.e. a closed cone)

A cone has 1 edge

Exercise

Object��������������� Number of vertices��� Number of edges����� Number of faces

1. Maggi cube
2. Die
3. Concrete block
4. Tin of milk
5. Football
6. Sugar cube
7. Ice-cream cone
8. Box
9. Class-room

Exercise 1

Study the pictures above and on page 251 along with other solid objects around the class

and classify them into open and closed objects.

Observations

1. Open object do not have a cover at the top. The inside of an open object can be seen,

because it has no cover or top face.

2. The inside of a close object cannot be seen because of the cover or top face.

Study this table carefully

�������� �������������������������Open object���������������������������� Closed object

Cube No of vertices��������� 8���������������������������������������� ��8

No of edges�������������������� 12���������������������������������������� 12

No of faces������������ �����������5����������������������������������������� 6

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Cuboid No of vertices������� 8����������������������������������������� 8

No of edges��������������������� 12��������������������������������������� 12

No of faces����������������������� 5���������� ��������������������������������6

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Cylinder No of curved faces 1��������������������������������������� 1

No of flat faces�������� �������������1�������������������������������������� 2

No of vertices����������������������� 0������������������������������ ��������0

Note:

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1. Tubes, pipes, straws are special cylinders with no flat face. They are known as hollow

cylinders. The two ends are open.

2. A sphere is always a closed objects.

Exercise 2

Copy and complete this table, stating whether the following solids are open or closed objects.

Name of shape���� Open����������� Closed

Bucket

Cup

Refrigerator

Ice-cream cone

Ludo die

Cube of sugar

Tin of milk

Tin of Milo

Tin of tomato

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1. Copy and complete the table drawn below.

Number of faces���� Number of edges������ Number of vertices

closed cube

closed cuboid

open cube

open cuboid

closed cylinder

open cylinder

sphere

cone

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Copy and complete the following.

1. A three-dimensional shape having equal faces _____________.
2. A cuboid has _____________ unequal faces.
3. The face of a cuboid is a _____________.
4. A cylinder has _____________ flat circular faces.
5. A cone has _____________ edge.
6. An open shoe box has _____________ faces