Number Systems ss 1 plan

LESSON PLAN: NUMBER SYSTEMS

Subject:	Digital Technologies
Class:	SSS 1
Term:	First Term
Week:	3
Topic:	Number Systems
Duration:	80 Minutes (Double Period)
Subtopics:	Binary number system; Decimal number system; Octal number system; Hexadecimal number system; Conversion between number systems.

BEHAVIOURAL OBJECTIVES

By the end of the lesson, students should be able to:

1. Define a number system.
2. Explain the meaning of the base or radix of a number system.
3. Identify the decimal, binary, octal and hexadecimal number systems.
4. State the base and symbols used in each of the four common number systems.
5. Explain why computers use the binary number system.
6. Convert simple binary numbers to decimal numbers.
7. Convert simple decimal numbers to binary numbers.
8. Convert simple decimal numbers to octal and hexadecimal numbers.
9. Perform simple conversions between selected number systems.
10. Apply place-value principles when working with different number systems.

INSTRUCTIONAL / TEACHING AIDS

• Number-system charts.
• Whiteboard and markers.
• Calculators.
• Computers or digital devices.
• Number-system conversion worksheets.
• Place-value charts.
• Projector or interactive display, where available.
• Prepared examples showing binary, decimal, octal and hexadecimal numbers.

PREVIOUS KNOWLEDGE / ENTRY BEHAVIOUR

Students are already familiar with ordinary counting and the decimal number system used in everyday life. They have also learned that computers process information electronically and that digital technologies use numerical representations. The teacher will build on this knowledge to introduce other number systems used in computing.

PRESENTATION STEPS

STEP	TEACHER'S ACTIVITY	STUDENTS' ACTIVITY
1. Introduction	The teacher writes numbers such as 25, 1010, 17 and A3 on the board and asks students whether all these numbers belong to the same number system. The teacher introduces the concept of number systems.	Students observe the examples and discuss how the numbers differ from the ordinary decimal numbers they commonly use.
2. Meaning of Number System	The teacher explains that a number system is a method of representing numbers using a defined set of symbols and a base. The teacher introduces the term base/radix.	Students listen, write the definition and identify the base of familiar decimal numbers.
3. Decimal Number System	The teacher explains that the decimal system has base 10 and uses the digits 0 to 9. The teacher demonstrates place values using examples such as 5,432.	Students identify the digits used in the decimal system and determine the place value of selected digits in given numbers.
4. Binary Number System	The teacher introduces the binary number system as base 2. The teacher explains that binary uses only 0 and 1 and demonstrates binary place values such as 1, 2, 4, 8, 16 and 32.	Students identify the two binary digits and practise writing binary place values. They convert simple binary numbers to decimal numbers with guidance.
5. Octal Number System	The teacher explains that the octal system has base 8 and uses digits 0 to 7. Examples are used to demonstrate octal place values.	Students identify the valid digits in the octal system and work through simple examples.
6. Hexadecimal Number System	The teacher explains that hexadecimal has base 16. The symbols 0–9 and A–F are introduced, with A representing 10, B representing 11, through F representing 15.	Students write the hexadecimal symbols and identify the decimal values represented by A–F.
7. Comparison of Number Systems	The teacher presents a comparison table showing the base, symbols and common uses of decimal, binary, octal and hexadecimal systems.	Students copy the comparison table and identify the differences among the four systems.
8. Number Conversion	The teacher demonstrates conversion from binary to decimal using place values and conversion from decimal to binary using repeated division by 2. Simple examples are solved step-by-step.	Students follow the worked examples and solve simple conversion exercises individually and in pairs.
9. Practical Exercise	The teacher gives students a short worksheet containing binary, decimal, octal and hexadecimal conversion questions. The teacher moves around the class to provide assistance.	Students solve the exercises and compare their answers with classmates.
10. Evaluation and Summary	The teacher asks oral questions, reviews the conversion methods and summarizes the major number systems and their bases.	Students answer questions, correct their work and explain the conversion methods in their own words.

EVALUATION QUESTIONS

1. What is a number system?
2. What is meant by the base or radix of a number system?
3. State the base of the decimal number system.
4. What digits are used in the binary number system?
5. State the base of the octal number system.
6. Which symbols are used in the hexadecimal number system?
7. Convert 1011₂ to decimal.
8. Convert 11001₂ to decimal.
9. Convert 13₁₀ to binary.
10. State one reason why the binary number system is important in computing.

ASSIGNMENT

1. Define the term number system and explain the meaning of base.
2. State the base and symbols used by the binary, decimal, octal and hexadecimal number systems.
3. Convert the following binary numbers to decimal: 101₂, 1101₂ and 10110₂.
4. Convert the following decimal numbers to binary: 7₁₀, 12₁₀ and 20₁₀.
5. Write the hexadecimal equivalents of the decimal numbers 10, 11, 12, 13, 14 and 15.

TEACHER'S REFLECTION

Students should be able to identify the four common number systems and explain their bases and symbols. Particular attention should be given to place-value concepts and conversion procedures, as students may require additional practice when converting between number systems. Additional worked examples and exercises should be provided for students who experience difficulty.