Lesson Plan

• Describe why sound must be digitised and how sampling converts an analogue waveform into binary data.
• Explain the relationship between sample rate, the Nyquist theorem, and the highest reproducible frequency.
• Calculate the data size of an audio file using sample rate, bit depth, duration and number of channels.
• Compare how different sample rates and bit depths affect audio quality, file size and processing load.
• Choose appropriate sampling parameters for a given IGCSE project constraint.

• Projector or interactive whiteboard
• Computer with audio editing software (e.g., Audacity)
• Sample audio clips at various sample rates/bit depths
• Worksheet with calculation exercises
• Calculator
• Handout summarising formulas and key concepts

Begin with a short video of a high‑fidelity music clip followed by the same clip played at a low sample rate to hook interest. Ask students what they notice and link it to prior knowledge of binary data. State that by the end of the lesson they will be able to explain and calculate how digital sound is stored.

1. Do‑now (5') – Quick quiz on analog vs. digital sound concepts.
2. Mini‑lecture (10') – Explain sampling, sample rate, Nyquist theorem, and bit depth with formulae.
3. Demonstration (8') – Show a waveform being sampled; play audio at 8 kHz, 44.1 kHz, and 96 kHz.
4. Guided practice (12') – Students calculate file sizes for given mono and stereo scenarios using the provided worksheet.
5. Group activity (10') – Design a simple game sound plan: choose sample rate/bit depth balancing quality and file size.
6. Check for understanding (5') – Exit‑ticket question: “If you need a 3‑minute stereo track under 5 MB, what sample settings would you select and why?”

Recap the key relationships between sample rate, bit depth, audio quality and data size. Collect exit tickets to gauge understanding and assign a short homework task to research real‑world audio standards for different media.