# History of Computer – Early Mechanical Calculating Device – Difference Engine (Primary 3)

COMPUTER STUDIES

(INFORMATION TECHNOLOGY)

BASIC SCIENCE AND TECHNOLOGY

FIRST TERM

WEEK 7

PRIMARY 3

THEME – BASIC COMPUTER OPERATIONS

PREVIOUS LESSON – History of Computer – Early Mechanical Calculating Device – Pascaline or Pascal’s Calculator (Primary 3)

TOPIC – HISTORY OF COMPUTER

LEARNING AREA

1. Introductory Activities

2. Early Mechanical Calculating Device – Difference Engine

3. Practical Class on how to use Difference Engine

PERFORMANCE OBJECTIVES

By the end of the lesson, the pupils should have attained the following objectives (cognitive, affective and psychomotor) and should be able to –

1. identify Difference Engine  among all early mechanical calculating devices

2. describe Difference Engine  counting device.

3. operate Difference Engine  counting device.

ENTRY BEHAVIOUR

Counting Devices

INSTRUCTIONAL MATERIALS

The teacher will teach the lesson with the aid of:

Chart showing Difference Engine

METHOD OF TEACHING – Choose a suitable and appropriate methods for the lessons.

Note – Irrespective of choosing methods of teaching, always introduce an activities that will arouse pupil’s interest or lead them to the lessons.

REFERENCE MATERIALS

1. Scheme of Work

2. 9 – Years Basic Education Curriculum

3. Course Book

4. All Relevant Material

5. Online Information

CONTENT OF THE LESSON

INTRODUCTORY ACTIVITIES

Teacher’s/Pupil’s Review on Pascal’s Calculator

EARLY MECHANICAL CALCULATING DEVICE – DIFFERENCE ENGINE

Teacher’s/Pupil’s Activities – Displays Analytical Engine  (if available) or a chart showing Analytical Engine for the pupils to observe and describe.

DIFFERENCE ENGINE

Difference Engine is a mechanical calculator that can compute several sets of numbers and making a hard copies of the results.

PRACTICAL DEMONSTRATION USING DIFFERENCE ENGINE FOR BASIC ARITHMETIC SUCH ADDITION AND SUBTRACTION

Teacher’s/Pupil’s Activities – if the device is available, call for expert if you are unable to operate the device or watch YouTube video how to use the device.

PRESENTATION

To deliver the lesson, the teacher adopts the following steps:

1. To introduce the lesson, the teacher revises the previous lesson. Based on this, he/she asks the pupils some questions;

2. Shows pictures of Difference Engine  computing device to the class.

Pupil’s Activities – Bring pictures/cut outs of Difference Engine  computing devices.

3. Demonstrates the use of Difference Engine .

Pupil’s Activities – Use the Difference Engine to solve different arithmetic problems.

CONCLUSION

• To conclude the lesson for the week, the teacher revises the entire lesson and links it to the following week’s lesson.

LESSON EVALUATION

Pupils to:

1. identify Difference Engine among all early mechanical calculating devices

2. describe Difference Engine counting device.

3. operate Difference Engine counting device.