SoundKids: An Interactive Web Application for Teaching Digital Audio to Children

SoundKids is an interactive, browser-based educational web application that introduces the fundamental concepts of digital audio to children aged 6 to 10. Motivated by evidence that early exposure to structured sound and music supports phonological awareness, working memory, and mathematical reasoning, yet remains unevenly accessible, SoundKids turns abstract audio concepts into something children can hear, see, and manipulate in real time, using only a modern web browser. The interface is styled as a cartoon television set with four themed channels, each teaching a core principle: waveforms (sine, square, triangle, sawtooth), audio filtering (lowpass, highpass, bandpass), additive synthesis, and speech synthesis. Built entirely with standard web technologies (HTML5, CSS3, JavaScript, the Web Audio API via Tone.js, the Web Speech API, and the Canvas API), it runs from a single self-contained HTML file with no server or build step. Real-time canvas waveform visualisation links auditory and visual perception, making the building blocks of digital audio explorable, audible, and immediate. The paper documents the architecture, the four interactive stations and their audio graphs, and the design rationale.