Technologies Support Materials
Assessment Principle 4
Assessment should be designed to meet their specific purposes
Engineering principles and systems snapshot: Rubber band Speed
Technologies/Design and Technologies/Knowledge and understanding/Engineering principles and systems and Processes and production skills/Investigating and defining/Designing
Forces and the properties of materials affect the behaviour of a product or system
Define a sequence of steps to design a solution for a given task
Identify and choose the appropriate resources from a given set
Develop and communicate design ideas and decisions using annotated drawings and appropriate technical terms
Nature of the assessment
Teacher observation of students’ investigations
Purposes of the assessment
Students implement design changes to improve the performance of their car by applying their knowledge about forces and properties of materials.
Students identify when changes do not lead to improved performance and determine alternative changes.
Stage in the Teaching sequence
A whole class activity in the middle of a teaching cycle – formative assessment
Students built a basic elastic-band powered car and then investigated changes to the design to improve performance.
Students had previously constructed an elastic band car (pull-back) and had tested that it works.
Prior to the investigation, the teacher showed her students a video clip that showed how to build a basic, elastic band powered car. Students worked in pairs to design and build their own car, and measure the distance it was able to travel.
The students were then given time to investigate what changes they could make to their car to see if they could make it go further. The teacher gave them the following series of questions to guide them through the process.
Elastic band powered car
How far did your car go?
Draw a diagram of your car and use labels to explain what makes your car go.
What changes can you make to your car to make it go further?
Make one change to your car. Write down the change.
How far did it go?
Did the change make your car further? Why do you think it worked/didn’t work?
Make another change to your car. Write down the change.
How far did it go?
Did this change make your car go further? Why do you think it worked/didn’t work?
Draw a design of an elastic band powered car that you think would go a long way. Label the diagram to explain why you think it would go a long way.
Using the information
The teacher observed the students as they worked. She spoke with students to check their understanding of the concept that forces and behaviours of materials affect the behaviour of the product. She looked at their notes to see if they had annotated their diagrams to explain their design ideas. While she corrected their spelling, she did not allow her assessment of their writing or of their drawing ability to affect her assessment of their understandings of Design and Technologies.
She used her observations to inform her planning of the next lesson.