Year 9 Science – Term 4 (WA Curriculum): Sound, Light and Scientific Investigation

What this unit covers

In Term 4, Year 9 Science in the WA Curriculum centres on the unit “Sound, Light and Scientific Investigation”.

Students explore the properties of sound and light waves through hands-on investigations, developing scientific inquiry skills while examining real-world applications and technological advances.

Lesson sequence (30 lessons)

The unit breaks down into the following lesson-by-lesson sequence — each title below is a teachable lesson, in order:

1. Investigating Sound Speed in Different Materials
2. Lightning and Thunder: Why We See Before We Hear
3. Planning Fair Test Investigations for Sound Experiments
4. Measuring Sound Speed Using Digital Equipment
5. Sound Reflection and Echo Formation
6. Exploring Echolocation in Nature and Technology
7. Resonance in Musical Instruments Investigation
8. Analysing Sound Wave Data and Patterns
9. Ultrasound Applications in Medicine
10. Seismic Surveying and Sound Wave Technology
11. Introduction to Light Reflection from Plane Mirrors
12. Investigating Curved Mirror Image Formation
13. Light Refraction Through Different Materials
14. Concave and Convex Lens Investigations
15. Proposing Hypotheses for Light Behaviour Questions
16. Planning Risk Assessments for Light Experiments
17. Using Light Meters to Collect Precise Data
18. Constructing Ray Diagrams and Data Tables
19. How the Human Eye Focuses Light
20. Correcting Vision Defects with Lenses
21. Analysing Light Experiment Results and Anomalies
22. Evaluating Data Quality in Optical Investigations
23. Constructing Arguments About Light Behaviour
24. Reporting on Sound and Light Investigations
25. Computer Modelling in Scientific Predictions
26. Australian Technological Advances: Cochlear Implants
27. The Bionic Eye: Science and Engineering Solutions
28. Marie Curie's Discoveries and Medical Applications
29. Climate Change Technologies: Solar Panels and Light
30. Contemporary Issues: Sound Pollution and Society

Curriculum codes in this unit

Content codes:

Reading the codes: WA codes (the ones starting with WA) pack the year level, learning area, strand and content number into one string, while the national Australian Curriculum v9 uses a different anatomy that starts with AC9 — same content family, different labels. Our complete WA Curriculum guide decodes both, character by character.

Planning notes for Term 4

WA terms run roughly 9–11 weeks, and in 2026 Term 4 runs from Monday 12 October to Thursday 17 December — 10 weeks for WA public schools. With 30 lessons in this unit, that leaves breathing room for assessment, moderation and the weeks that disappear to carnivals, camps and public holidays — plan the assessable work to land two to three weeks before the end of term rather than in the final week.