Data Representation - SSS 1 Lesson Plan

LESSON PLAN: DATA REPRESENTATION

Subject	Digital Technologies
Class	SSS 1
Term	First Term
Week	10
Topic	Data Representation
Duration	80 Minutes (Double Period)
Subtopics	Bits and bytes; ASCII; Unicode; Image representation; Sound representation.

BEHAVIOURAL OBJECTIVES

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

1. Explain the meaning of data representation.
2. Define a bit and a byte.
3. Explain how text is represented in a computer system.
4. Define ASCII and explain its purpose.
5. Explain Unicode and its importance in modern digital systems.
6. Explain how digital images are represented using pixels.
7. Explain how sound is converted from analogue to digital form.
8. Explain the meaning of sample rate and bit depth.
9. Differentiate between the representation of text, images and sound.

INSTRUCTIONAL / TEACHING AIDS

• Computer or laptop
• Projector or interactive display
• Charts showing binary digits and bytes
• ASCII character chart
• Unicode examples
• Digital images or photographs
• Audio recording or sound file
• Whiteboard and markers
• Smartphone or tablet where available

PREVIOUS KNOWLEDGE / ENTRY BEHAVIOUR

Students have previously learned about number systems and understand that computers use binary numbers. They have also learned about computer hardware, software and storage devices and should understand that computers need data in a form that can be digitally processed.

PRESENTATION STEPS

STEP	TEACHER'S ACTIVITY	STUDENTS' ACTIVITY
1. Introduction	The teacher displays different forms of information such as text, an image and a sound recording. The teacher asks how a computer can store and process these different forms of information.	Students identify the different forms of data and suggest how a computer might store them.
2. Meaning of Data Representation	The teacher explains data representation as the way digital systems encode, store, process and communicate information. The teacher emphasizes that computers ultimately use binary data.	Students listen, ask questions and write the definition of data representation.
3. Bits and Bytes	The teacher explains that a bit is a binary digit with a value of 0 or 1 and that eight bits make one byte. The teacher gives simple examples of digital storage units.	Students define bit and byte and answer simple questions involving the relationship between them.
4. Text Representation	The teacher explains that characters are assigned numerical codes which are stored and processed digitally. ASCII is introduced as a character encoding standard.	Students explain how characters can be represented using numerical codes and identify examples from an ASCII chart.
5. ASCII	The teacher explains the meaning of ASCII and introduces its standard 7-bit character set. Examples such as A, B, a, b and numerical characters are discussed.	Students identify selected ASCII characters and explain the purpose of character encoding.
6. Unicode	The teacher explains Unicode and why it is necessary for representing characters from many languages and writing systems. Examples of multilingual text are displayed.	Students compare ASCII and Unicode and explain why Unicode is useful for international digital communication.
7. Image Representation	The teacher displays a digital image and explains that images are made up of pixels. The teacher introduces resolution and colour representation, including RGB.	Students identify pixels and explain the meaning of image resolution and RGB colour representation.
8. Sound Representation	The teacher explains that sound must be converted from analogue form into digital data. Sampling, sample rate and bit depth are introduced.	Students explain sampling and identify factors that affect the storage requirements of digital sound.
9. Comparison Activity	The teacher asks students to compare how text, images and sound are represented in a computer system.	Students work in groups to complete a comparison table showing the representation of text, images and sound.
10. Conclusion	The teacher reviews bits and bytes, ASCII, Unicode, image representation and sound representation. The teacher corrects misconceptions and summarizes the lesson.	Students answer oral questions and summarize the major concepts learned.

EVALUATION QUESTIONS

1. What is data representation?
2. Define a bit and a byte.
3. How many bits make one byte?
4. What does ASCII stand for?
5. State two differences between ASCII and Unicode.
6. Why is Unicode important?
7. What is a pixel?
8. Explain how an image is represented digitally.
9. What is sampling in digital audio?
10. State three factors that can affect the size of a digital audio file.

ASSIGNMENT

1. Explain data representation and state why it is important in digital technology.
2. Define bit and byte and explain their relationship.
3. Explain ASCII and Unicode and state three differences between them.
4. Explain how digital images are represented using pixels.
5. Explain how analogue sound is converted into digital form.

TEACHER'S REFLECTION

The teacher should assess whether students understand how different forms of information are represented digitally. Particular attention should be given to students' understanding of bits and bytes, ASCII, Unicode, pixels, sampling, sample rate and bit depth. The teacher should identify areas where additional practical demonstrations or exercises are required.