Early Calculating Mechanical Device ( Basic 3 First Term Week 3 )

History of computer II

Subject   :  Computer Studies


Class  : Basic  3 / Primary 3  / Year 3


Term : First   Term


Week  : Week 3


Topic  :

Mechanical counting devices



Previous Knowledge : The pupils have previous knowledge of


History of Computer ( Basic 3 )


that was taught  in their previous lesson.



Behavioural  Objectives : At the end of the lesson , learners will be able to

  • Say the history of Computer
  • identify early counting devices
  • state four early counting device



Instructional Materials 

  • Wall charts
  • Pictures
  • Online Resource
  • Textbooks
  • Early Counting Devices like Abacus


Methods of Teaching 

  • Role modelling
  • Questions and Answers
  • Explanation
  • Discussion
  • Recitation
  • Imitation
  • Story Telling
  • Dramatization


Content : 



The first computer was called the Abacus counting machine.

Early mechanical counting devices and their inventors


The first computer was made several years ago by a man called Abacus. It was used for simple additions and subtractions.

It is known as the Abacus counting machine.


Other early inventions that were discovered and useful for counting are

..1. Pascal Machine

.2 . Slide ruler

3. Analytical machine

4. Abacus


Pioneers Of Early Mechanical calculating Machines 

Blaise Pascal : A Frenchman called Blaise Pascal made the first adding machine in 1642. It was a very big machine. Blaise Pascal’s father used this machine in recording taxes collected and spent by the government.


Sir Samuel Morland: Sir Samuel Morland, an Englishman, invented three calculating machines between 1663 and

1666. The first one was used for addition and subtraction of money. The other two were used for more difficult arithmetic.



Charles Babbage : Charles Babbage, another Englishman, made the first machine that calculates and stores information. His computer was better than an ordinary calculator. It was a very big machine.



Presentation  : 

The topic is presented step by step

Step 1 : The class teacher revises the old topic

Step 2 : The class teacher introduces the new topic

Step 3 : The class teacher allows the pupils to give their own contributions and gives room for pupils” participation


Class Teacher And Pupils Activities. Interaction or  Participation 

This involves class teacher  and pupils interaction , conversation , imitation or modeling through discussion , play method or just by recitation or asking and answering questions that are related to the topic that has just been taught

  • The class teacher asks the pupils to bring some small stones for counting
  • The pupils are asked to bring sample Abacus to class
  • Pupils are encouraged to describe the use of the abacus




  1. What is a computer device?
  2. What device do we use to receive information?
  3. What did the early people use to count?
  4. The first adding machine was invented in what year?
  5. Abacus is use for……………. And …………….
  6. Mention four early counting devices
  7. Name five counting devices people used before the invention of computer.
  8. Write to inventors, their invention and the use of their invention.