Ask eight-year-olds what they want to be when they grow up and chances are you won’t hear them say scientist, technologist, engineer or mathematician. The gap between children’s perception of science, technology, engineering and mathematics (Stem) and the exciting life they envisage for themselves is just too great.
So it makes good sense to reverse this perception and awaken young minds to the idea that Stem can be exciting, cool, meaningful and important for our world.
Stem comes alive with group work, where teachers are able to cross subject boundaries and develop projects with real-world applications, rather than being limited by time and curriculum constraints. The primary curriculum provides more chances for cross-curricular work and hence presents a wonderful opportunity to make Stem subjects relevant to younger pupils.
In my novel Catching Infinity, the eight-year-old protagonist’s life changes for ever when he sees a generator being rigged up in the foreman’s house and a light bulb flickering to life: for the first time, the boy realises that there is a relationship between the things we are familiar with and the unseen.
Similarly, in my teaching, I often put topics and projects into a real-world context, to begin cultivating my students’ interest and instilling in them the belief that they are part of the solution.
Communicating concepts
The four issues facing this generation (and, most likely, the next) are energy, the environment, communications and food production. As the medium of communication has changed so dramatically over the past two decades and is very much at the forefront of young people’s lives, I have started with that.
The following activities are suitable for Years 5 and 6, although they can be simplified for younger age groups. The objective is to get students to grasp the concept that sound is an integral part of our everyday sensory experience; to learn how it is made, transferred, received and stored; and, in a broader context, to work out how it affects our lives and our forefathers’.
The learning objectives are:
- vibrations;
- medium;
- sound wave;
- frequency;
- pitch;
- amplitude.
Making sound waves
The propagation of sound waves is the basis for communication. It is a difficult concept to grasp for pupils at the beginning of their Stem journey but nonetheless it represents one of the entry points into associating the unseen world with physical reality.
One of the most visually compelling ways to show young students the concept of moving sound waves is by using a Slinky. The movement of the springed toy represents sound wave compressions and rarefactions, and helps demonstrate to students that sound is created by vibrating objects.
Morse code is another simple but compelling way to bring Stem topics into the classroom, in this case electromagnetism and coding. To demonstrate how “dits” and “dahs” became the foundations of a complex system of communication during the Second World War, teachers can create their own Morse code kit by wrapping a piece of magnet wire around a nail and using it to make a paper clip move in response to an electrical current flowing in the wire. (Morse code kits are also available for purchase.)
Then there is the wireless telegraph, the forefather of all digital communications. Building simple telegraph kits in class is a practical way of showing students how to convey text (“graphic”) information over distance. In addition to the learning objectives listed above, this project also introduces the following concepts:
- analogue and digital signals;
- transmission medium;
- carrier;
- encoding/decoding;
- modulation/demodulation;
- gain/attenuation;
- base (signal) bandwidth;
- broadcast bandwidth;
- noise/distortion;
- multiplexer/demultiplexer;
- time division multiplexing;
- frequency division multiplexing;
- error detection/error correction;
- the relationship between bandwidth, data rate and the capacity to carry information.
Introducing concepts that are normally first addressed in GCSE electronics to younger pupils may at first glance seem too complicated. However, if you keep your explanations simple, primary students will understand these ideas at a basic level, and they often relish big words.
Putting communication into context
Explaining the history of developments in communication puts Stem into context, as well as providing interesting discussion points and research topics to show students that Stem is the bedrock of humanity’s evolution and progress.
In opening a discourse on smartphones, you can take students as far back as the days when people used smoke signals to communicate long-distance. Using this primitive method of communication, our forebears were able to share news, warn of danger or gather people at a specific meeting place.
However, its limits forced people to develop new technologies capable of sending and receiving messages more reliably, more accurately and, perhaps most importantly, encoded so that only their recipient could read them.
This leads naturally onto a discussion of the use of Morse code during the Second World War and the development of the telegraph system, and a comparison of the strengths and weaknesses of each.
You might also like to share the story of Thomas Edison. Perhaps best known for the invention of the light bulb, the inventor and his colleague, Ezra T Gilliland, also patented an ingenious method of communication. The imaginatively named grasshopper telegraph allowed Morse code signals to be sent back and forth from moving trains to fixed telegraph systems by means of electrical induction. This was the early forefather of radio communications, and the ancestor of the smartphone that we hold in our hands today.
Modern-day applications
Now your students know about the history of communications, you can add further “real world” relevance by asking them to compare mobile packages between different service providers. This is a good opportunity to teach students (even at the early key stages) about gathering data, building spreadsheets and interpreting the numbers, which is the foundation of science at secondary level.
Jacqueline Koay teaches physics and chemistry as a subject specialist
