Design and Technology, Digital and STEM

By Roni Malek

Way back in 2009, the Science Learning Centres collaborated with DATA (the Design and Technology Association), RAEng (the Royal Academy of Engineering) and a range of people from  Design and Technology (D&T )and STEM (Science, Technology, Engineering ,Maths) communities to develop Continuous Professional Development (CPD) for Secondary Design and Technology (D&T) teachers in the area of systems and control. Over the years things have developed to cover other topics such as Smart materials and eTextiles and we also now have an online eCPD offering.

DATA and others had identified a range of issues including a long term trend of falling numbers of 15 year olds taking D&T. Most schools were designing and making in ‘the food and resistant materials and textiles’ aspects of the programme of study but relatively few, about 7%, in the ‘systems and control’ aspect using new technologies and STEM contexts.

The two CPD courses, Make it Work and Make it Move, were developed for D&T teachers who had no previous experience of electronics so that they could learn skills, ideas and pedagogy to develop confidence in delivering systems and control in their classrooms, typically at KS3 and KS4.

In the Make it Work course teachers learn basics of electronic components and circuits, solder and assemble a Cyberpet board, based on a PIC (Peripheral Interface Controller) chip. Teachers also program the Cyberpet to detect the switch and light sensor inputs and operate LED and buzzer outputs, for example to simulate a flashing bicycle light. Many other projects are possible: electronic pet, light sensitive security buzzer or night light, tune playing greeting card, variable program steady hand game…

Make it Move extends the use of programmable control to actuation – teachers learn about issues in connecting circuits to electric motors and gears to create programmable moving projects. The example used in the course is a bubble blower, programmed to drive two motors which again can be the basis of other projects.

Both courses have a STEM slant including input from a STEM ambassador to show real world applications of these technologies. In one Make it Work course our STEM Ambassador was from Transport for London and showed the use of PIC type circuits to run tests on traffic lights. In Make it Move a STEM Ambassador from Hitachi Trains described how actuation was used to control brakes, toilet doors and other train systems. Science related to D&T is also covered to show how important Science and D&T are to each other in the real world and to promote collaboration in school.

Make it Move now has an on-line version and there is also an on-line eTextiles course. Teachers enrolling on these courses are sent resources for making and complete the required study on-line in their own time with support from an experienced tutor.

Follow up support from the Digital D&T centres is also available as it was recognised from the outset that teachers would need time and support after the courses to develop their skills and get further ideas.

Another course, Collaborative Learning in Science and Design and Technology is aimed at D&T and science teachers attending together to develop and plan cross curricular work (I’d like to get maths teachers as well!). The course looks at issues and ideas for working across the subjects. It is commonly run on a Smart materials theme but can use other examples. For example at a recent course in an East London School with four D&T and eight science teachers we tried out a range of examples such as comparing crumple zones and measuring the energy consumption of lighting and other electrical devices.

Product analysis of torch parts and construction is a common example in D&T but energy consumption is rarely analysed. The science department has the equipment needed to do this but more importantly for learning, uses the language of energy. The use of  Joules and Watts in both science and D&T leads to better science understanding from working with real contexts and better, more technologically rigorous design. Energy consumption and efficiency are of course two essential design parameters for today’s world.

Courses may be run at Science Learning Centres or by arrangement as outreach at schools. The importance of D&T courses is recognised in our programme with the course fees being supported by our Impact awards for teachers from state maintained schools.

Links
Details of the range of Science Learning Centre D&T courses https://www.sciencelearningcentres.org.uk/audience/secondary/design-technology - only here will you find out what the TTDTT acronym stands for but much more importantly you’ll find links to all the above courses which we hope you will use to invigorate your D&T and STEM curriculum.

Design and Technology Association – http://www.data.org.uk/ and http://www.believeindandt.org.uk/

I stole the “technologically rigorous” quote from someone called James Dyson. It’s in his Ingenious Britain report which you can find scrolling down here http://www.jamesdysonfoundation.com/about/education.asp

How fresh are your fruits? – A gas measurement exercise

By Richard Needham

This is a simple exercise involving measuring gases, which reveals some surprising secrets. It can give rise to interesting discussions around what we mean as scientists by the term ‘living’.

You can do this activity at any level in school – the data you collect could be used:

• Key Stage 1 – as a way of classifying fruits

• Key Stage 2 – what we mean by living and non-living

• Key Stage 3 – measuring respiration rates

• Key Stage 4 – planning investigations and photosynthesis

• Post-16 – investigating the effect of variables on biochemical reactions

I collected the data shown here at home in the kitchen one wet Sunday, so no special facilities are needed. I used a plastic box with two holes in the lid – one for a carbon dioxide sensor and one for an oxygen sensor. Mrs N kindly provided a couple of unripe avocado pears, which just fitted inside the box. I was surprised at how much carbon dioxide they released within a few minutes.

Measuring the respiration of an avocado

The graph below shows just how quickly the atmosphere inside the box changes. Note the gradients of the lines are difficult to compare as oxygen is measured as a percentage, whilst carbon dioxide is measured in parts per million.

Changes to oxygen gas (%) and carbon dioxide gas (ppm) over 60 minutes with single avocado

So are avocados unique? No they are not, as all the fruits I tested absorbed oxygen and gave out carbon dioxide. Some are far more active than others. For example my bananas absorbed oxygen three times faster than avocados. Grapes were slowest, again a result that surprised me as they have a huge surface area, and thin skins. When I measured gas exchange in grapes there was hardly any change shown after ten minutes. In the chart below, the data point for grapes is partially hidden by ‘apples’.

Gas exhange comparisons in fruits

Equipment used

1. Vernier bio chamber, with gaseous oxygen and carbon dioxide sensors attached to a laptop via a Labquest mini USB interface.

1. Vernier Logger Pro software for data collection and initial analysis, and then used Google docs to produce the comparative graph of results.

You should get similar results with any oxygen and carbon dioxide sensors providing they measure gaseous concentrations rather than dissolved gas. A sandwich box or ice cream container could be used in place of a proprietary bio chamber.

Questions and opinions that arose in discussions with colleagues

• Surely fruits are dead once they are picked from the tree?

Several colleagues assumed that once picked, a fruit becomes ‘dead’. Thinking about the ripening processes that continue this cannot be the case. However, some people assumed that the gas exchange shown in the data was a consequence of microorganisms and rotting processes.

•  But a mushroom is not a fruit.

To a biologist a mushroom cannot be a fruit as it is not a plant and does not possess the organs required for fruit development. Sometimes mushrooms are described as fruiting bodies (of basidiomycete fungi) and so I have no hesitation in justifying their inclusion in this investigation. Interestingly the data point for the mushrooms lies well below the line expected if these results are to be explained by aerobic respiration alone.

•  Why don’t green ones produce oxygen?

I initially thought that green fruits would be photosynthesizing, and produce very different results to those shown here. There is no way to tell if photosynthesis did influence the results, unless some further work is carried out, such as repeating at different light intensities.

•  How did you make it a fair test?

Good question. I am against the notion that scientific investigations always need to be fair tests. I did use similar masses of fruit in each case (about 420g) but did not attempt to control the effects of surface area.

•  Why would you want to do this?

I enjoy finding out things that are not readily explained by the science we teach in school. It challenges me to think deeper about what I am teaching, and leads to better understanding through discussion with others. Using sensors is one way of uncovering new information, and often turns up results that are unexpected.

And of course: Well how do you explain the results?

I will leave that question for you to answer.

Some useful links to help with your answers or planning

SAPS – Respiration and photosynthesis made easy

STEM elibrary- photosynthesis

Comments

I would be interested to hear your explanations for these results.

I would also like to know if these results are repeatable.

Also, do you have any examples of other ways that sensors can turn up unexpected results?

Life in the Labs – Data Loggers

by Helen Rose

In this, the first of my video blogs, I am introducing  data loggers; what they are, how they can be used and what to consider when buying data loggers for your school.  In later video blogs I’ll be showing you what data loggers are available in the market and some of their individual features and benefits.

Life in the Lab -Data loggers 1

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