Sound Wave Studio

Overview

In this lesson (7 of 25) students investigate how sound waves show up in pitch, loudness and timbre. They use the PhET “Sound Waves” simulation alongside real instruments/tuning forks to compare virtual wave behaviour with real-world sound.

Learning intentions

• Students will explain properties and behaviours of sound waves, linking them to measurable wave features.
• Students will describe how changes to frequency affect pitch, and how changes to amplitude relate to loudness.
• Students will compare timbre using waveform/visual cues from recordings and identify what a “sound signature” suggests about a sound source.
• Students will communicate a short scientific argument using evidence from simulation results and a real instrument.

Success criteria

• I can identify frequency and amplitude in a sound-wave representation and state what each means for pitch and loudness.
• I can use evidence from PhET and a real recording to support claims about pitch and loudness.
• I can describe how timbre differs even when pitch and loudness are similar.
• I can use scientific language (frequency, amplitude, waveform, pitch, loudness, timbre) in a conclusion.

Curriculum links

• PY-11-02 — Students explain the properties and behaviours of waves (focus on sound-wave properties and behaviours).
• PY-11WS-07 — Students communicate scientific arguments using evidence, scientific language and terminology for a specific audience.
• PY-11WS-04 — Students select and process qualitative and quantitative data and information (recording/analysing features such as frequency and relative amplitude).
• Focus context: Sound wave properties and behaviours in everyday situations (instruments, tuning forks, audio recordings).

Lesson structure (45 minutes)

1. 0–5 min · Starter (connect to real sound). Teacher plays a short clip of the same note from two instruments (or teacher strums two strings) and asks students: “What stays the same, what changes?” Students quick-write two observations and one question.

2. 5–12 min · Mini direct teach (wave-to-sound mapping). Teacher introduces the idea that sound waves are longitudinal, and that recordings/waveforms show patterns related to frequency and amplitude; timbre links to the complexity of the sound. Students copy a 3-column table: Pitch → (frequency), Loudness → (amplitude), Timbre → (waveform complexity/overtones).

3. 12–23 min · PhET station: pitch and frequency. Teacher demonstrates in PhET how changing frequency changes the sound heard and the wave pattern; students follow with one controlled change and record results in their table. Students use a simple data sheet: “Frequency set to __ Hz; perceived pitch: higher/lower; waveform spacing: closer/further.”

4. 23–31 min · Real instruments: validate pitch & loudness. In groups, students use either a tuning fork (if available) and/or a simple instrument (e.g., guitar string, keyboard note, xylophone). Teacher prompts: keep pitch constant as much as possible, then increase force/volume and observe loudness changes; then try changing pitch (e.g., different string or tuning fork). Students record: what they changed, what they heard, and what they predict the waveform would do (spacing and relative height).

5. 31–40 min · Audio analysis comparison (evidence for claims). Teacher assigns each group one recording to analyse using a device tool (phone/tablet audio app or provided software) to identify frequency and observe waveform amplitude differences; students compare their recorded waveform features with the PhET screenshots/notes. Students highlight one “match” (evidence consistent across both) and one “difference/complication” (e.g., timbre complexity, room reflections).

6. 40–45 min · Exit ticket (scientific argument). Teacher asks for a 4–5 sentence response: “Using evidence from PhET and your recording, explain how you know frequency controls pitch and amplitude controls loudness. Include one sentence about timbre.” Students submit individually.

Resources

• Devices (laptops/tablets) with PhET “Sound Waves” accessible
• Prepared PhET guide sheet (step-by-step settings for frequency/amplitude changes)
• Audio recording tool on devices (basic waveform view if available)
• Tuning forks (where possible), mallets, stands/mounts
• Simple instruments or sound sources (guitar strings, keyboard, xylophone, drum)
• Group data sheets for recording: frequency, relative amplitude/loudness, observations about timbre
• Safety reminders for tuning forks and instrument handling
• Optional: phone-based timer for standardising “how long the note is played”

Assessment

• Formative: Teacher circulates during PhET tasks checking students’ tables for correct mapping (frequency→pitch, amplitude→loudness).
• Formative: During instrument testing, teacher listens for correct qualitative claims (higher frequency → higher pitch; stronger strike → louder sound).
• Formative + summative-in-mini: Exit ticket uses a claim-evidence-reasoning structure, assessed for scientific language and correct linking of wave properties to sound perceptions.

Differentiation

• Support: Provide sentence starters for the exit ticket (e.g., “The frequency controls pitch because…”, “In our recording, the waveform showed… which indicates…”).
• Support: Give group roles (Recorder, Equipment controller, Simulation operator, Evidence checker) to reduce confusion and increase engagement.
• Extension: For students ready to go further, ask them to compare two sounds with similar pitch/loudness and propose what timbre difference might be indicating (e.g., additional frequency components/shape changes).
• EAL/SEN: Keep instructions short and visual; allow students to submit exit tickets using bullet points if needed, while still using key terms.