Strategies for teaching technological products
Year 6 and 7 students at Dilworth School (a decile 4 independent boys' scholarship school) worked within different contexts (Jewellery and Ergonomic Knives), but both units focused on the technological products component of the technological knowledge strand. Teacher Sarah Blenkiron used a variety of strategies to introduce them to the concepts of "performance properties" and "fitness for purpose".
Metal Jewellery unit
In the Metal Jewellery unit, the first year 6 project of the year, students developed their own pieces of jewellery. They were given the opportunity to create a souvenir item in metal. Sarah says there was a wide range of outcomes. "The fact that it's in metal, they think it's great, they loved the unit." The students designed and created individual metal jewellery; their outcomes included key rings, pendants, and necklaces.
During this unit of work the class focused on two of the technology curriculum components: technological products and characteristics of technological outcomes. Sarah found that there were clear links between these two components, as both involved students in investigating the links between the physical nature of a product, including its materials, and the function of that product. (See Strategies for teaching characteristics of technological outcomes.)
Where appropriate, encourage the use of all five senses.
For the technological products focus, Sarah began by introducing her students to the concept of performance properties through a matching activity in which they examined a wide variety of hard and soft materials (including cards, fabrics, metals, plastics, and woods).
Students were encouraged to play with, feel, and smell the material samples. They then matched the different materials with words describing performance properties (for example, translucent, brittle, absorbent, sharp, stretchy).
Sarah notes that some of the descriptions are more subjective than others, which is okay because having words that describe both objective and subjective properties can support student understanding of performance properties.
Explore understandings of material performance properties through practical experiences.
After looking at discrete material samples, Sarah brought in different kinds of jewellery made from a range of materials for the students to examine. They had to describe the performance properties of the materials used, not the attributes of the jewellery piece itself. They then considered how each was shaped, joined, and finished*, which led to them deciding what its function would be.
Sarah further developed the students' understanding of material properties within the context of metal jewellery. She gave each student some metal samples to test and trial. Sarah says she used aluminium, brass, and copper, because they are the most easily available in sheet form and because they have different properties. The students tested how these performed for snipping, filing, drilling, punching, and engraving purposes. This testing helped them decide which material would be best for their own product, because some liked a firmer metal for cutting or a softer one for shaping. Sarah comments, "So all the properties we'd talked about started to come through in that activity and it worked really well."
Ergonomic Knives unit
The year 7 Ergonomic Knives unit explored the ideas within the technological modelling and technological products components. Students developed a range of 3D functional models of knives from Plasticine, clay, and Styrofoam, giving them the opportunity to explore the properties of materials used for modelling purposes.
Sarah had read the Technology Online Craft Knives case study, which led to her developing this unit of work.
Sarah approached "properties" slightly differently with this group. Instead of looking at lots of materials and matching them with cards, the students first brainstormed what performance properties might be. They then looked at samples of metals, plastics, woods, and fabrics and considered their performance properties.
After considering performance properties in general, the class looked at them in a more specific context. Sarah gave each student an old craft knife, which they disassembled so that they could explore its components and the materials used. After identifying the parts of the knife, the students listed the different materials it was made from. They then listed the performance properties of those materials and described why they thought those materials were chosen. (See Performance properties worksheet.)
Determine a products function and purpose through analysing its material(s) properties.
The students then examined a wide variety of knives, the purpose of some being obvious and others more obscure.
Sarah notes that some people were astounded that she let eleven-year-old boys loose with extremely sharp knives, but all she had to do was discuss her concerns with them and the room was blood-free after 75 students had handled all the knives!
After examining the knives (Sarah provided pictures of them as well), the students had to identify if the materials in each knife had been shaped, joined or finished*and how that had been done. They also had to try and guess the exact function of each knife. Once they had guessed the knife's function, the students decided if it was fit for purpose for that presumed function.
The real function of each knife was shared later. Sarah notes that the boys did struggle with making a decision on each knife's fitness for purpose, but improved once they were reminded to consider the materials chosen and how those materials had been shaped, joined, and finished, as clues.
The boys were really keen about both projects because the materials they were using were new to them. This encouraged them when learning about the performance properties. The year 6 students, for example, had not used metal before. This unit gave them a good chance to learn new skills, learn about the materials, and learn how they could use materials and manipulate them. Having hands-on activities with real knives, though obviously with care, worked really well. The students needed to be able to feel and touch the different materials.
Sarah introduced her students to the concept of material performance properties by giving them the opportunity to explore material samples and see how these transferred into products. This meant they could feel, smell, and maybe even taste the different materials. Encouraging students to feel, play with, and pull apart products and material samples is a valuable teaching strategy, not only within the technological products component, but also within other components such as characteristics of technological outcomes and technological systems.
Properties describe materials and attributes describe technological outcomes.
It is important to use the correct vocabulary so as not to confuse students. Sarah found that, when describing the properties of the materials used in a piece of jewellery, some students described the attributes of the jewellery piece itself instead. This is an easy trap, as sometimes the properties of a material (for example, nylon is waterproof) are also the attributes of the technological outcome (for example, the toiletry bag is waterproof). Starting the exploration of properties by looking at samples of material, separate from actual products, can help prevent this confusion. In addition, it is essential that teachers use the terms "properties " and "attributes " correctly – properties are the features of materials and attributes are the features of technological outcomes.
* Update: After this unit was taught, the 2010 Indicators of Progression replaced the terms "shaped", "joined" and "finished" with the terms "manipulation", "transformation" and "formulation". (See Level 4 Technological Products Flowchart.)