JSS 3 First Term

LEARNING OBJECTIVES: BY THE END OF THE LESSON PUPILS SHOULD BE ABLE TO:

Cognitive	i. Explain place value in the decimal and binary systems. ii. Convert numbers between decimal, binary and hexadecimal. iii. Describe the octal system and what it is used for. iv. Explain why computers use the binary system.
Affective	i. Appreciate the value of Number Systems in school, at home and in the community. ii. Show willingness to use digital tools carefully, safely and responsibly.
Psychomotor	i. Write the place values of the binary number 1101 and convert it to decimal. ii. Convert the decimal number 13 to binary by repeated division. iii. Convert the binary number 10110101 to hexadecimal. iv. Write the hexadecimal digits and their decimal values from 0 to F.

Rationale: A number system is a way of representing numbers using a specific base and a set of digits. Understanding starter Scenario, what is a Number System, the Binary System, converting Decimal to Binary helps learners use digital technology confidently, safely and responsibly.

Pre-requisite Knowledge: In Week 4, learners studied Network Devices and Protocols, including network Devices in Depth, network Protocols, tCP/IP. The knowledge from that week is used again in this lesson.

Learning Material/Teaching Aid: Whiteboard, markers, computer or laptop where available, printed notes and charts on Number Systems, practical task sheets, learners' notebooks and pens.

Reference Materials: Digital Technology for Junior Secondary Schools (JSS 3); NERDC Digital Technology Curriculum; Digital Technology JSS 3 First Term Notes (Week 5); First Term examination and Continuous Assessment question papers.

LESSON DEVELOPMENT

Stage/Step (Time)	Teacher's Activities	Student's Activities	Learning Points
Introduction 5 MINUTES	Welcomes learners, revises Week 4 (Network Devices and Protocols) with two quick oral questions, and asks what they already know about Number Systems. Elicits responses and writes the topic on the board.	Recall the previous lesson and share what they already know about Number Systems.	Connecting prior knowledge to Number Systems.
Step 1 6 MINUTES	Covers Starter Scenario: Amina's younger brother asks her, how does a computer count, it does not have fingers like we do. Amina thinks about her ten fingers and the decimal system she uses for counting, then wonders how a machine with only electrical signals can represent numbers at all. Covers What is a Number System: A number system is a way of representing numbers using a specific base and a set of digits. The base of a number system tells you how many distinct digits it uses and how the value of each position increases.	Listen, take notes and answer oral questions on "Starter Scenario" and related points.	Understanding: Starter Scenario; What is a Number System.
Step 2 6 MINUTES	Covers The Binary System: The binary system is base 2, using only two digits, 0 and 1. Each position in a binary number represents a power of 2. Covers Converting Decimal to Binary: To convert a decimal number to binary, repeatedly divide by 2 and record the remainders. The remainders, read from bottom to top, give the binary number.	Copy the key points, give examples from school and everyday life, and ask questions on "The Binary System" and related points.	Understanding: The Binary System; Converting Decimal to Binary.
Step 3 6 MINUTES	Covers The Octal System: The octal system is base 8, using digits from 0 to 7. Each position represents a power of 8. Covers The Hexadecimal System: The hexadecimal system, often called hex, is base 16, using the digits 0 to 9 and the letters A, B, C, D, E and F. The letters stand for the decimal values 10, 11, 12, 13, 14 and 15.	Discuss in pairs, then report one point on "The Octal System" and related points to the class.	Understanding: The Octal System; The Hexadecimal System.
Step 4 6 MINUTES	Covers Converting Between Systems: There are three main conversion directions learners should master. To convert binary to decimal, multiply each binary digit by its place value and add the results.	Respond to questions, complete the examples on the board and note down "Converting Between Systems".	Understanding: Converting Between Systems.
Practical Work 6 MINUTES	Guides learners through the practical work: (i) Write the place values of the binary number 1101 and convert it to decimal. (ii) Convert the decimal number 13 to binary by repeated division. (iii) Convert the binary number 10110101 to hexadecimal. Moves round the class to check progress and correct unsafe or careless use.	Carry out the practical tasks individually or in pairs and record what they did in their notebooks.	Applying the lesson through hands-on practice.
Evaluation 3 MINUTES	Asks learners to: i. Explain place value in the decimal and binary systems. ii. Convert numbers between decimal, binary and hexadecimal. iii. Describe the octal system and what it is used for. iv. Explain why computers use the binary system.	Respond verbally and in writing to the evaluation questions.	Assessment and consolidation of the lesson content.
Conclusion 2 MINUTES	Recaps the main points: starter Scenario, what is a Number System, the Binary System, converting Decimal to Binary, the Octal System. Links them to the assignment and previews Week 6: Binary Numbers and Data Representation.	Listen, ask questions and copy the assignment.	Reinforcement of key concepts and a preview of the next lesson.

Assignment: i. A computer stores the number 1011 in binary. A pupil says this is the same as one thousand and eleven in decimal. Convert 1011 from binary to decimal to show the pupil the correct answer. ii. A school wants to label 16 network cables from 0 to 15 using hexadecimal numbers. Write out the 16 labels and explain why hexadecimal is shorter than using binary for the same labels.