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26.5.08

Explanatory Texts From a Multimodal Starting Point

As a class this term we have been reading the Amanda Mitchison Biography "Who was... ? Isambard Kingdom Brunel." The story even though a challenge in places has fascinated the students. The book has proven to be a fantastic stimulus for discussion about the "great man of Iron" but when combined with web based images and tools has also stimulated high quality talk for writing in support of mechanism based explanatory texts .

Of Worms and Men..

The tunnelling shield invented by Brunel's father, appeared in the opening chapter of the biography and was a great starting point for discussion, one which began with Marc Brunel's observing ship worms at Chatham Docks, before inspiring his idea to dig tunnels through a process of removing spoil, inching men forward in a protective shell and lining with bricks the space behind them as they work. This principle is still employed in modern tunneling, and the enormous tunnel boring machines we see today work on a similar basis. The use of modern control technologies, machine automation of processes, global positioning and monitoring and sensing technologies may have improved navigational accuracy, speeded up the process, but it is no less dangerous today than in the past, spoil still must be removed and the machinery maintained, driven and programs planned, miners still scurry around in the spaces between the tool and the tunnel, lining it as the machine edges forward. The system has advanced, but even as the technology charges on, the principles of its evolution and in many ways its operation remain similar to those originated in Brunel's time. A need is identified, available designs and tools explored affordances exploited to identify possible solutions, before adaptations or innovations are made on these to create a product that either meets our needs, or carries us forward into the unknown. As we have read Brunel's story together I have tried to be mindful of this in the discussions we have had, not only talking about the great man's life and works, but also exploring the similarities between old and new technologies. Not only is this a valuable place to be in terms of historical investigation, comparing past and present, but an essential process based conversation to have in light of a DT curriculum in the England that requires students to engage as designers and makers through Investigation Dissassembly and Evaluation Processes, and an ICT curriculum that requires a similar set of processes to evolve beyond the skills based aspects of the curriculum in developing ideas and exploring the impact of ICT on everyday life.

In terms of Literacy development the formal use of terms relating to "cause and effect" are not common place in the talk that we use or encounter. The written genre of explanation requires us to write from an impersonal perspective and to use "Causal Connectives" such as "this causes, " "as a result," and so on. Taking an impersonal view of the action we are describing can be a real challenge, I remember myself writing science experiments up for the first time at secondary school and being reminded constantly that I needed to use impersonal pronouns while I tried to explain the process as if I wasn't involved. In essence this made the difference between my report being an explanatory text and a set of instructions or a recount. In talking about diagrams such as the tunnelling shield I began the process of modelling the language structures the students needed to hear, that would help them rehearse the written work they would use later. Recording these on the diagrams we explored as a flow chart.

Eg
Men standing in the shield dug out the soil and rock, which was thrown to the ground.
Labourers loaded the spoil into barrows, that were used to carry it out of the tunnel.
As the shield moved forward, the tunnel was lined with bricks, this helped support the roof... and so on.

As the students became more familiar with the sound of the genre, we began to collect some of the words and phrases we were using to display on our word wall.

Converging Technologies

For the last couple of weeks we have been using our literacy sessions to extend our experiences of writing explanatory texts while exploring how some of the technologies that enabled Brunel's visions to emerge worked. We focussed on steam engines and Steam Locomotives technologies Brunel did not invent but was keen to adapt and exploit in his endeavours. To explore the principles behind turning up and down movements into rotary movement to drive ships such as the great Eastern and Western we explored how stationary pumping engines worked. "North Star" one of the first locomotives to run on the Great Western Railway was built at Robert Stephenson's works in Newcastle, and as we had found some amazing material online about Stephenson's Rocket we decided to use this as a model to help us find out about how Brunel's locomotives worked.

Multimodal Starting Points Using Talk to Promote Writing

Within this unit although using some written texts initially to support how the features of an explanatory text are presented and work, most of our activity involved making and using models, and exploring video presentations and animations to help the talk for writing process. During the first week we used videos from Espresso, to share visual and audio descriptions of the processes involved in powering a Bolton and Watt Stationary Beam Engine. We used these video texts to scaffold and rehearse verbal explanations of how the engine worked. As a class we made cardboard models, including linkages and a background diagram of the engine to help us create the link between our talk and the writing we would later engage in. As the children worked with these they were encouraged to talk about share and rehearse with their partners their growing understanding of how these machines worked, gradually being encouraged to expand and present their oral explanations to include a range of sentence openers from our word wall and to begin including the causal connectives they would need to use in their written captions for presentation later in the week. The children were very excitied by the quality of the modelled outcomes they produced, but I was also really impressed by the quality of written outcome produced.

The second week, of activity involved the students in expanding the process previously worked on by creating a similar model of Stephenson's Rocket. We began with the image below left, before the students began creating their own background diagrams similar to that on the right. The students were given a cut out drive wheel to begin with, and the large wheel space at the front drawn in as their starting point. While discussing the source image we also identified that this drive wheel would be where our mechanism would be added to the diagram later in order to give a sense of scale to their drawings.

To support the sessions as the week progressed we used this nice Flash animation from the BBC website as our stimulus for talking for writing. It helped us decide what the mechanism we needed would look like, and to pick out the four key processes we would include. The Steps in our explanation would be

1) Firing up the engine (how the water was heated)
2) Water turning to steam (why the water was heated)
3) Steam forces down the Piston (what the steam was for)
4) The drive shaft turns the wheel (the outcome of all this effort)

On completion of the diagram and mechanism the children were encouraged to explain the process orally to partners and rehearse the captions they would add.
They were challenged to use a variety of sentence openers interestingly several of the students used time connectives they had collected in previous writing session and units to do this. Among the success criteria for the activity was also the need to use the causal connectives we had collected link action with outcome in their model as they described them. I have been really excited by the quality of the children's work. I haven't any photographs of the outcomes from this activity yet, but will include an example or two later. Combining multimodal text use, talk for writing and animated mechanisms however did have a dramatic effect on the way the students finally presented their outcomes. Linking the use of DT to model the process not only gave context to scaffold talk for writing but beyond the DT and literacy based experiences gained from this series of activities, the students were also helped to make links between this and their science work on forces using magnets and springs, and to apply language developed here in their ICT unit on control as we explored how input brings about output.

Image Credits:
Tunnelling Shield from Wikipaedia
Stephenson's Rocket Cutaway From BBC
Student work and outcomes SDMills

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