Jumpstart the junk in Computing

By Phillip Anley posted 20-03-2023 12:35


Teachers love to reuse old materials. That can take the form of previous lesson plans, tinsel or posters with curled up edges rolled up in the back of a cupboard for the next time a topic is visited.

Computing teachers are no exception. We also need to cover the same learning objectives each year. Livening up that old familiar content adds fun, and presents an opportunity.

The Computer Science curriculum requires pupils to be taught, and more importantly to understand, what is inside a computer, and how it works.

From DIMM memory modules to the inner workings of old SATA hard disks – these are concepts best revealed through hands on experience. Most schools that teach computer science, and some that don’t, retain a cupboard of old computer parts. These vary from the impressively ancient (a dusty Acorn badge or roller-ball mouse can sometimes be spotted) to the almost current: a graphics card that once cost £400 but is not now Direct X capable for the latest gameplay.

By the time twenty eager hands have brushed static electricity over them, their fate is sealed: no longer parts for upgrade, now relics – artefacts of what was once a living, functioning computer system.

So many PCs were produced in the years that followed the ‘dot-com’ bubble, that there will not be a shortage of such demonstration parts for a very long time. Billions of computers scattered throughout the dusty offices, bedrooms and garages of untold millions of IT practitioners has resulted in a glut – a deluge - of PC technology. 

Those of us who are old enough remember the 1990s when PCs cost more; were bigger; slower and less common. Even some of those still survive (full disclosure: I keep one running!) yet once the Pentium 3 era arrived, with DVDs and the newly accessible Internet – the explosion in take up was rapid. Suddenly everyone wanted a PC (or a translucent Mac) to multitask their day.

Only the arrival of mobile phones – also conveniently boasting the Internet, but with easier to operate apps in place of unwieldy applications – could begin to slow PC dominance.

Cue mountains of discarded mobile phones, many of them hundreds of times more powerful than the PCs that came before.

Much has been written about the eWaste situation on our planet. It is now understood more widely that rare earth resources are being wasted; that poorer nations are being used as dumping grounds and that the health of many is threatened by environmental pollutants stemming from the toxic chemicals contained within these devices.

From a teaching perspective it might be thought that educating the next generation about the situation: stark facts and worrying maps, is all that can be done at this stage. That, and using up some old PC components to explain the inner workings of personal computers.

More can be done

Physical computing’s time has come. It describes a range of methods that bring teaching to life through connectivity and practical use of existing technology.

Where once teaching was for the most part abstract: think rows of wooden desks with children copying down established facts at a remove from the content - now it must be experienced.

Teachers know that ‘chalk and talk’ (didactic) delivery is not effective or even efficient. It wastes everybody’s time. Pupils do not enjoy being talked at for long periods by teachers. They react by switching off, disengaging and turn their focus to the tree outside or perhaps a spider lazily spinning a web in the corner of the classroom.

Children engage with learning by doing; problem solving; applying their skills and their own resourcefulness to accomplish a given task.

Headteachers these days are on the lookout for targeted questioning; retrieval practice and, above all, interested pupils.

Teachers want to deliver fun and interesting lessons. It is not enjoyable or rewarding to be stuck in front of thirty eager faces all of whom expect the next hour to be an interesting, productive and worthwhile endeavour – if the materials on which that lesson is based are flat, tired and uninspiring.

Junk can make for great lessons

To be clear, I am not just talking about Computing here.Every subject can benefit from hands-on, connected equipment. This is the very same hulking mass of wires, screens, buttons and batteries that would otherwise be heading to landfill. 

Reduce, Reuse, Recycle: there is an abundance of old technology just waiting to be deployed in schools, if the leadership of those schools are willing to be bold and adventurous with what is already freely available to them.

If it conducts, then it can be connected. If it can be connected then it can be coded. If it can be coded then it has a new potential existence. All that is needed is a new vision for that old tech – an awareness of how it can be brought into fresh classroom context.

Teachers are imaginative. They like to explore new options. There is an opportunity for Physical Computing to reenergise our lessons where progressive teaching can be matched by innovation in the ways that technology, old and new alike, is leveraged for maximum pupil benefit.

The missing link here is an understanding of how to connect these devices up so that they can be programmed anew. It is not that difficult and, once shown how, teachers can apply the same skill to any number of educational scenarios.

School CPD improves the skills base for teachers in many subjects. Physical Computing skills are value-added because they cross departmental boundaries. 

Great teacher support organisations such as STEM Learning and the National Centre for Computing Education exist to provide and promote new approaches to learning. Marrying up the best pedagogy with a new, low-cost resourcing opportunity is surely a welcome enhancement for teachers.

It’s important to emphasise that only low voltages – which pose no danger – are ever used. Although the equipment may once have been mains voltage powered (ie 240 volts), to use it again in a classroom environment it must necessarily be kept within a safe voltage. I use four types of kit for connecting, and thus being able to code, the recycled equipment:

Raspberry Pi

The latter of these, Raspberry Pi, is the most expensive but also has the greatest potential. The others cost in the region of £20.

We teach our pupils to code using visual coding systems such as Scratch / Make Code or using text level, for example, Python. All of these interfacing kits work with all of those coding options.

Each creates a link: conductivity then code

The difference is concrete over abstract. Rather than looking at a screen for the output, pupils can see something much more exciting happen:

Science experiments incorporate sensors, materials and outdoor-capable structures that would otherwise not have featured in the laboratory stores.

PE races are triggered and recorded through ingenious contraptions on the playing field.

In the second decade of the 21st century, I feel so privileged to be teaching at a time of technological plenty.

Those old iPads can still do wondrous things. The motors in that toy car can move a robot. Meters, gauges and dials can record information anew.

Let’s use the excess ‘junk’ to inspire pupils, and in so doing let’s avoid waste.

For more information about Physical Computing, or to become involved in the Space To Learn / Tinker initiatives head to the Flickernet site

Did you enjoy this blog? If so, scroll to the top and hit the 'Recommend' button!




04-04-2023 16:31

Great article - allied to this is the subject of retro computing. Computing now has a rich history and I am rather addicted to the YouTube videos that look at retro computing - the 8-bit processors of the 1980s that are, in some respects, a lot easier to understand (I am from that time I should mention). A problem with today is that the students are taught basic computing on systems that are wildly more complex than the knowledge they are being asked to learn in KS3/KS4. I am tempted to say that learning how a computer worked (from a processor perspective) would be a lot easier on a Z80 or 6502 processor. If I can get hold of an old machine, I would be tempted to show students

1) how different computing was when I was there age
2) how easy it is to do certain things that nowadays appear a lot more complex.

The peeks/pokes of a Commodore C64 and learning to write compact code to fit within a small amount of RAM were challenging to say the least but it was also fun. I am not advocating just teaching 8-bit computing, but I do think that a lesson that shows how computing once was can help place some context around how we got to where we are. Equally, I think it is possible to show the significant benefits of modern processor architecture by comparing how they have changed (e.g., use of cache memory, etc, 64 bit architecture, etc).

03-04-2023 21:46

I like this. Perhaps companies with redundant machine can pass these to colleges for practical learning with students rather than just send to the crusher for metal recycling. Reuse first would be much more valuable and cost effective.  College students gain a lot of learning from practical experience dealing with real equipment.