Technological systems
The purpose of the Technological systems component is to support students to develop logical capabilities, by understanding why and how systems work the way they do, then to apply this knowledge when they design and develop their own systems.
A technological system is a set of interconnected components that has been designed to fulfil a particular function without further human design input.
Technological systems transform, store, transport, or control materials, energy, and/or information for a particular purpose.
A door mechanism is an example of a system made of material parts that are controlled to allow a door to open and close. Computer code is an example of an information system where the lines of code direct the computer to carry out instructions. Generating power using hydro-electricity is an example of a system that controls and transforms the energy of moving water into electricity.
In any system, how the parts work together is as important as their individual characteristics.
In order for students to design their own systems, it is important they understand systems concepts:
- input, output, transformation, and control
- "black box”
- redundancy and reliability
- operational parameters.
Examples
These illustrative examples demonstrate how skills and understandings related to the technological systems component could be developed at different school levels.
Learning experiences
The following learning experiences have been provided to support teachers as they develop their understanding of the technological systems component of the technological knowledge strand.
There is no expectation that these would form the basis of any specific programme of learning in technology. The learning experiences have been summarised from classrooms across New Zealand and provide examples of student achievement across a range of levels.
Junior primary
Students could explore a range of familiar technological systems (such as an electric jug, a windup toy, yoghurt maker, television, computer, fish tank, popcorn maker, washing machine, torch, pacemaker, and so on) and identify the components of the system and what it has been designed to do.
Teachers could lead a discussion about technological systems and explore what they have in common with, and how they differ from, natural systems, for example, the digestive system, and social systems, for example, the lunch ordering system at school.
The teacher and students could select an example from the familiar systems above and together discuss what the inputs, outputs, and transformation processes are. They could also explore how the system ensures that the transformation occurs in a controlled fashion. In pairs, the students could select their own example and identify its inputs and outputs, controls, and transformation processes. Allowing students to use the systems would aid these explorations, as would being able to pull some apart where appropriate.
As part of class discussions, students could suggest definitions for a technological system to enable them to distinguish technological systems from non-technological systems and begin to explore why the same technological outcome may be referred to as a technological system or a technological product.
Students achieving at level 1 could be expected to identify the:
- components of a system and how they connect to each other
- inputs and outputs of a system and that a transformation of some sort has occurred.
Students achieving at level 2 could be expected to describe the:
- change that has happened (the transformation process) to an input for the output to be produced in a simple system
- role each component has in the transformation of the input to output in a simple system.
Senior primary
First, students could identify a number of simple technological systems from different contexts.
Afther that they could represent the parts of the systems using appropriate language tools (including graphical symbols) for the type of system focussed on.
Next, students could categorise the systems explored – are they transforming energy, information, or materials?
Then, students could explore a more complex technological system that consists of one or more black boxed components, (for example, a security system, manufacturing system, car wash, fermentation system, and so on) and discuss the advantages and disadvantages of not knowing what is happening inside the box.
In order to gain a better understanding of the concept of black boxes and technological systems, students could make a bread product. As part of their technological practice, allow them to experience a variety of ways of making bread.
That is, they could make bread in a traditional way – accessing their own ingredients and carrying out the steps by hand, whereby their design input is necessary for the transformation to occur. In this case, bread making is not a technological system.
Another option is they could then make bread with a bread-maker and access their own ingredients. In this case, the bread-maker is a technological system – but its system nature can be viewed as a black box as its transformation processes are hidden.
Finally, the students could make bread with a bread-maker using a ready bread mix. In this case, the bread-maker (a technological system) and the mix (an input into this system) can both be thought of as black boxes.
The students could also view a video showing a commercial bread factory and identify technological systems employed in this context.
They could explore the nature of the outputs in all these scenarios and determine the ratio of wanted (bread product) versus unwanted (waste, energy depletion, pollution, and so on) outputs in each case.
Ongoing class discussions could be held around the quality and reliability of the end product, and how easy it was for the student to modify the product to allow for different tastes and so on, within each method used. Students could complete a PMI (plus, minus, and interesting) analysis of making bread in a variety of ways.
Students achieving at level 3 could be expected to:
- describe a range of simple technological systems (including a system involved in bread making) using appropriate language tools
- explain what a black box is, and give examples of how a black box can be both helpful and unhelpful.
Students achieving at level 4 could be expected to:
- identify an example of a control mechanism within a technological system and explain how it influences the transformation process
- describe how the fitness for purpose of the bread-maker was and/or could be enhanced by the use of control mechanisms.
Junior secondary
Students could investigate the computer network within their school to identify and explore how it meets both technical feasibility and social acceptability specifications.
They could also identify subsystems within the system, establish the transformation and connectivity properties of these, and the interface implications for effective integration into the system. Students could explore the way that the system has been designed so that failure in a particular subsystem is managed to guard against overall system failure and/or damage. This may be by way of alternative paths or shutdown options.
Extensive investigation could be undertaken to uncover the workings of a black box within the identified system. Issues associated with ongoing support and maintenance could be explored and suggestions made for the different levels of expertise required to develop, use, maintain, and repair their school computer systems.
Students achieving at level 3 could be expected to:
- describe the system using appropriate symbols and language to represent its components and connections
- identify examples of black boxes within the system and suggest how these may be viewed differently by members of the school community.
Students achieving at level 4 could be expected to:
- identify control mechanisms within the system and explain how they influence different transformations
- explain how control mechanisms enhance the system's fitness for purpose
- communicate, using specialised language and drawings, system-related details that would allow others to create a feasible and acceptable network system.
Students achieving at level 5 could be expected to:
- identify all subsystems within the system and explain their transformation and connectivity properties
- discuss how the interface between each subsystem allows the system to work together effectively.
Senior secondary
As part of student involvement in the development of an electronic game, they could focus on developing understandings associated with micro-controllers (for example, Arduino/Raspberry Pi).
Undertaking product analysis of a number of everyday appliances allows students to begin to explore the nature of the transformation processes occurring within what was previously the system black box when viewing the appliance as a product. Once these processes are understood, students can practice writing software that would allow for these processes to occur.
Exploring a range of components (such as real-time clocks, micro-controllers, pulse-width-modulation blocks, motors, and so on) and the interfaces between them allows students to build up their systems knowledge related to subsystems, redundancy, and reliability that will support their design decisions for the development of their own game.
Students achieving at level 4 could be expected to:
- explain how the fitness for purpose of a particular appliance was enhanced
- communicate, using specialised language and drawings, system-related details to support their development of a feasible and acceptable outcome.
Students achieving at level 5 could be expected to:
- explain the specialised transformation processes occurring within components that serve as subsystems within an appliance
- discuss how electronic interfaces support the integration of subsystems in the development and maintenance of systems.
Students achieving at level 6 could be expected to:
- explain how multiple sub-systems allow for the development of systems with additional features
- describe examples of how outcomes allow for self-regulation to occur within a system.
Students achieving at level 7 could be expected to:
- explain how reliability was enhanced through the design, development, and maintenance of a particular technological system
- discuss examples of designed redundancy and explain why it was deemed necessary to enhance user safety.
Students achieving at level 8 could be expected to explain the:
- impact of energy efficiency and fail-safe on the operational parameters of systems used in familiar appliances
- operating parameters of an appliance and the implications of these for its design and ongoing maintenance requirements.
Technological systems: Key ideas (Word 2007, 31 KB)
Acknowledgment: This paper is derived from an earlier version by Dr Vicki Compton and Cliff Harwood.