A sequence to develop ideas about hearing
Classroom Activity for 5-11
Based on the Physics Narrative and the Teaching and Learning Issues
Hearing is a very significant sense to humans, and some sounds evoke strong emotional responses. The physicality of the sound is really important, both of making connections to the underpinning vibrations and for establishing a context for the learning and the emotional hooks. We therefore advise using physical sources, rather than recordings of sources, wherever possible.
Meeting reality: valuable experiences
- Noticing sounds from many different sources
- Hearing the wobble board in action
- Exploring collections of vibrating objects that make sounds of different loudnesses and pitches
- Semi-quantitative descriptions of the connection between different vibrating objects and the sounds that are heard
- Tracing out the paths of vibrations from source to detector
As many of these as possible should be direct physical experiences, rather than mediated through video or audio clips. This locates the learning in the lived-in world of the child, and grounds the learning in specific physical circumstances.
A sequence for developing the idea
This is a suggested sequence of activities, so a repertoire, on which to draw as you decide on a sequence to best suit the children in your own situation.
Brings children's attention the range and variety of sounds that can be heard in different places in their local environment. Executed so as to encourage beginning to think about and look for the sources of the sounds.
An exploratory activity to begin to develop a descriptive language for sound (recognising the many qualities of the sound in addition to the more universal, but also more refined and abstract, quantitative measures).
To begin to develop a shared description of sounds (drawn, spoken, enacted, maybe painted) in which you describe sounds. The interfaces for child-accessible apps for the creation of rhythm and melody might provide some stimulating starters. Such descriptions can be drawn on to begin to look for the sources of those sounds. Here electronic media don't provide such a rich suite of readily available metaphors and experiences. Richer physical experiences are more likely to support fruitful reasoning about the physical basis on which we hear.
This is a useful extension or reinforcement activity, that can draw on, and develop the shared descriptions.
This activity reinforces physical vibrations as the basis of sounds: so the need to set an object vibrating to make a sound, and the varying ways in which it can vibrate, and perhaps also some ways in which it can be set vibrating.
It's highly likely that a number of topics rely on hearing as an essential component: for example many stories revolve around what can be year, and what cannot. Drawing these, and any current news into accessible reasoning and reporting takes some doing, but the strengthening of the network of ideas can repay this input. This may be experiential, document
In this activity you can focus in on the idea that anything producing a sound must be vibrating. It starts off with sources that involve obvious vibrations and moves to sources with more subtle movements later.
Here you concentrate on the physical medium: connecting the source and the detector.
Sending messages using sound enables you to think about transmitting the vibrations and preserving the patterns of those vibrations.
This activity focusses on the route which the vibrations must follow from source to detector in order for a sound to be heard, and ways in which you can vary the route to alter that sound.
A design and suggest activity for varying the medium to affect the loudness of what is heard.
This can reinforce the relationship between pitch and frequency by measuring the range of hearing using computer generated sounds.
Here you can visit vibrations as the design of devices to detect sounds, including an outline structure of the ear, but also a functional description of microphones.
The speed of sound is used to measure distances – with a stopwatch. This has important links to many kinds of imaging, including ultrasound scans.
Here you use graphical plots, perhaps generated by a data logger, to tell stories about soundscapes with data.
Messages from research and practice: specific tripwires for this idea
There are several challenges to be met in teaching the sound topic, many of which revolve around the idea of vibrations that travel. We hear sounds, but you cannot point to the sound. The QuoteThis(sound) is really a name for a whole process.
As we begin to characterise sound , so separating out the loud and the quiet from the high pitch and the low pitch is facilitated by considered choice of descriptions and depictions.
All sounds are generated by the vibration of a source.
Hearing a sound necessarily involves the to-and-fro movement of a physical medium.
Sound can only
fill a space to the extent that it travels through that space.
Some children have the idea that sound is an entity that itself travels from speaker to ear. This view needs to be countered with the scientific view that sound is the name of a process, and not the name of an object.
Typically children are quite happy to say that sounds get quieter as they travel further away from the source and suggest they
die away. You'll need to encourage a more precise idea than this.
There are two separate simple ways of describing sounds, and you will need to help children differentiate between them.
These are reminders of, and links to, the Teaching and Learning Issues strand.
Representing and reasoning: doing physics
The source-medium-detector model, and the idea that vibrations travel from source to detector underpins a fruitful model of reasoning about sound.
Sound is a useful label for the whole process of the vibrations making this journey and being detected by us. The vibrations have to travel in something and so a physical medium is needed: this can be solid, liquid or a gas. As the vibrations travel away from the source, so they spread and the sounds we hear become quieter.
- source-medium-detector model established and used.
I hear a soundassociated with the process of vibrations travelling from source to detector via a medium.
- travelling vibrations accounting for reductions in loudness as you travel away from the source.
Find out more from the Physics Narrative.