LEARNINGFind the frequencies that bring order to the sand.
Before you tune: predict whether higher frequencies will make simpler or more complex patterns. Then test it.
Audience: curious learners ages 12 and up. No prior physics is required. Allow about 10–15 minutes for all four labs.
Learning outcomes: learners should be able to explain how frequency changes vibration patterns, relate simple frequency ratios to repeating motion, predict a beat rate from two nearby frequencies, and explain how harmonics alter timbre without changing the fundamental pitch.
Misconception addressed: “everything is frequency” is an evocative phrase, but it can blur important distinctions. This experience shows that many systems can oscillate while keeping sound, light, and matter scientifically distinct.
Facilitation prompts: Ask “What do you predict?”, “What evidence changed your mind?”, and “Can you make the opposite result?” Have pairs describe one change without naming the control and let a partner reproduce it.
Public beta · Design hypothesis, not proven effectiveness · Maintained by ACED · Last substantive update September 21, 2026. Representative learner testing is still pending.
Scientific references: Technorama: Sound Patterns; Exploratorium: Wave Upon Wave; OpenStax University Physics: Waves; and OpenStax University Physics: Sound.
All graphics and audio are calculated locally for this lab; no third-party media is embedded. Cymatic patterns are idealized illustrations rather than predictions for a specified plate. Lissajous motion is slowed. Interference shows a mixed signal; cancellation in a room depends on listening position. Tone Sculptor isolates harmonics and omits the changing attacks, noise, and body resonances of real instruments.
Learning Frontier and ACED names and marks are reserved. Free access does not grant a separate open-source, trademark, or media reuse license. External source links require internet access; the learning experience itself works offline.
Sound begins off. Every scientific relationship is also described in text and graphics. Use Tab or the five-button exhibit controller; sliders support arrow keys and no learning task requires dragging. The visible Motion control pauses automatic motion, and the experience honors your device’s reduced-motion preference. The canvas has a changing text description.
We target WCAG 2.2 AA. Keyboard, reduced-motion, responsive layout, audio headroom, and local/offline operation have been checked. Full screen-reader, contrast, 200% zoom, touch-device, and representative hardware reviews remain pending, so conformance is not yet claimed.
No account, name, email, cookie, application analytics, microphone, camera, or browser storage is used. Settings and discoveries remain only in the current page and reset after three idle minutes or a reload. The hosting platform may process ordinary access and operational data under its own policies.
To report an issue, describe the lab, what you expected, what happened, and your device or exhibit computer through Learning Frontier’s contact form. Do not include sensitive personal information.