Wave Behaviour Vocabulary

Applied vocabulary for wave behaviour (reflection, refraction, absorption, scattering, amplitude, wavelength, frequency, echo, spectrum, angle of incidence, angle of reflection) for ages 9–11. The teaching goal is precise, applied USE of a highly confusable term set, not rote definition: each word is taught against its nearest confusable neighbour on a single discriminator, and every term is immediately used to explain a real phenomenon (bent straw = refraction, echo = reflected sound, blue sky = scattering, prism = spectrum). Core discriminator: does the wave bounce back into the first medium (reflection), pass into a new medium and change direction at the boundary when it meets it at an angle (refraction), get sent off in many directions by a rough surface or by tiny particles such as those in air (scattering), or soak in and not return (absorption)? The three wave-property words pin to distinct features of one wave — amplitude = height from the middle (rest) line to a peak, wavelength = peak-to-peak distance, frequency = how many pass per second.

• Swapping reflection and refraction — treating light that crosses into a new medium (refraction) as if it bounces off it (reflection).
• Believing reflection is 'only mirrors' and refraction is 'only glass blocks', rather than every surface reflecting and any change of medium refracting.
• Reading 'bending' (refraction) as light travelling in a CURVE instead of a change from one straight-line path to another.
• Measuring the angle of incidence/reflection from the SURFACE rather than from the normal (the perpendicular).
• Blurring amplitude, wavelength and frequency into a vague single 'size' of the wave instead of three distinct measurable features.
• Not recognising absorption as an option (forcing every light–surface interaction into reflect or refract), and confusing scattering with plain mirror-like reflection.
• Treating an 'echo' as a mysterious separate effect rather than simply reflected sound.

• One incoming ray meeting a boundary with branching outcomes — bounce back (reflection), pass through and bend (refraction), soak in (absorption) — plus a rough-surface many-ray version (scattering).
• A single labelled wave with amplitude, wavelength and frequency each called out on its own distinct feature.
• A protractor drawn on the NORMAL showing angle of incidence = angle of reflection measured from the perpendicular.
• Everyday exemplar cards each pinned to one term: bent straw (refraction), canyon echo (reflection of sound), blue sky (scattering), prism rainbow (spectrum).

• Teach each term against its nearest confusable neighbour on ONE discriminator — bounce back (reflection) vs pass-through-and-bend (refraction) vs spray off a rough surface (scattering) vs soak in (absorption); remember air is usually the first medium.
• Pin the three wave-property words to distinct visual features of a single wave (amplitude = height, wavelength = peak-to-peak, frequency = number per second) and vary ONE at a time so the terms don't blur together.
• Confront the language traps explicitly: 'bending' in refraction is a change from one straight path to another (not a curve); reflection is not only mirrors; refraction is not only glass blocks.
• Define angle of incidence and angle of reflection from the NORMAL (the perpendicular to the surface), not from the surface itself — the classic measurement error.
• Use every term immediately in an explanation of a real phenomenon (bent straw = refraction, echo = reflected sound, blue sky = scattering, prism = spectrum), matching the DfE 'read, spell and USE scientific vocabulary' requirement.
• Support correct spelling with word-part cues (re-FLECT = turn/bounce back; re-FRACT = break/bend through; ab-SORB = soak in) to reduce reflection–refraction confusion.