First Term Lesson Note for Week Two
Class : Primary Two
Subject : Computer Studies
Topic : Revision / Historical Development of Computer.
Duration : 40 Minutes
Period : Single Period
Reference Book :
- Starters Companion Computer for Primary Schools, Book 2.
- Lagos State Unified schemes of work for lower Primary, (Primary 1 – 3).
- Online Resources
Instructional Material : Chart showing the early counting devices such as stones , fingers, toes, sticks, etc.
Learning Objectives : By the end of the lesson learners will be able to :
i. Identify the early counting devices
ii. Describe the early counting devices
Content :
Counting started with the use of stones, sticks, fingers and toes. It was recorded by history that the Babylon Ian’s were the first to count with stones. Herdsmen used stones to count their cattle by representing each with a stone. But these methods were slow and difficult, so man decided to look fir other ways of counting. As man progressed, the need for a much faster and easier method was discovered. This led to the invention of mechanical counting devices such as abacus, Napier’s bone, slide rule, Pascal’s wheel, analytical and difference machine.
Mechanical Counting Devices
A mechanical counting machine is a device used to perform basic operations of arithmetic automatically.
Abacus (500BC)
Abacus is a counting device that uses columns of beads and thread. It was invented later around 500 BC (Before Christ). This was the first mechanical counting device. The beads can be moved up and down the thread which allows addition and subtraction of Numbers.
Napier Bones (1617)
A scientist in the year 1617 invented a better calculating devices called Napier Bones. This was invented by a Scottish Mathematicians called John Napier. It contained some sets of bones on which numbers were written. The sets of bones were used for calculation such as multiplication of numbers.
The Slide Rule (1622)
William Oughtred invented the slide rule in 1622. It had two scales which slide over one another. It could only performed operations like multiplication and division. Slide rule is also known as slip stick.
Presentation Steps :
Step 1 : Revises the previous term’s work with the learners.
Step 2 : Introduces the new topic to the learners by explaining the early counting devices
Step 3 : Identify and list the early counting devices and describe what gave rise to inventions of mechanical devices.
Step 4 : Mention the mechanical counting devices, inventors and their uses.
Evaluation :
1. Counting by man started with the use of ____________, ______________, ___________ and ____________.
2. Another name for slide rule is _________ (a) beads and thread (b) bones (c) slip stick
3. ____________ is made with frame which holds a series of thread with beads fastened on them. (a) Abacus (b) Napier bones (c) Slide stick
4. Which mechanical counting devices is used to perform addition and subtraction? (a) Napier bones (b) Slide rule (c) Abacus
5. The Napier bones is a mechanical device used for calculation such as _____________. (a) addition and subtraction (b) multiplication (c) division and multiplication
6. List the inventors of these mechanical counting devices:
i. Slide rule : _____________________________
ii. Napier bones : ________________________
7. Why was the use of sticks, stones and toes for counting abandoned by man? (a) fast and easier (b) slow and difficult (c) I don’t know.
Conclusion : At the end of the lesson learners were able to answer the questions correctly.