How safe are your sunglasses?
Y10 (07/05) |
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a)
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i) ii) |
A (diagram shows small pupil relative to B) B (diagram shows larger pupil relative to A) |
easy easy |
b) |
Answers should include:
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difficult
very difficult |
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c) | C | difficult | |
d) | D | easy | |
e) | Don’t drive while wearing these glasses. | moderate | |
f) | Any explanation that links low levels of light entering eye to inability to see clearly enough to drive safely. | moderate |
Common misconceptions in question b). These included:
- Sunglasses can magnify UV light
- UV light gets trapped in the sunglasses.
- The whole eye gets bigger or smaller.
- Wearing low quality sunglasses represents the same situation as wearing no sunglasses.
- Confusion over the correct names for parts of the eye.
Indications of students' ability to explain and discuss
38 percent of the trial students answered question b) by essentially repeating the information provided, not adding any element of their own understanding to address the question. Very few students (6 percent) drew on their biological knowledge of the eye to introduce correct terms (e.g. "pupil") into their discussion. The question explicitly asks for students to use their own knowledge, and most correctly recognised the pupil reflex, so they did have some knowledge. This question could provide a useful opportunity for students to practise applying what they know to a new situation.
Knowledge of science/society interactions
Students appear to have very little understanding of the role of science and technology in determining safety standards:
- 14 percent thought the people who wear sunglasses should test them to see if they are safe.
- 6 percent thought the people who wear them should set the safety standard for sunglasses.
- 6 percent thought the people who sell sunglasses should test them to see if they are safe.
- 11 percent thought the people who sell them should set the safety standard for sunglasses.
Where students did recognise that these roles should be carried out by those with the knowledge and expertise (and lack of self-interest) to do so, they often confused the roles played by scientists and technicians.
- 47 percent thought scientists should test sunglasses to see if they are safe.
- 19 percent thought technicians should set the safety standard for sunglasses.
Links to the curriculum
A discussion of the issues raised by questions c) – f ) could help students link ideas about the role of science in setting and maintaining safety standards, to the integrating strands for the "nature of science" and for "participating and contributing" achievement objectives. Students could, for example, research how safety standards are devised and debated. This task also provides students with an opportunity to explore one way science is used to enhance public safety, in a situation where they could be expected to make good personal decisions now, or at any time in the future. This idea again links the question to the "participating and contributing" aim.
There are several avenues that could be pursued – either as next learning steps or as open questions in summative assessment.
- Do students recognise that they can use the information about safety standards to guide their own decision-making? Would they do so? Why or why not?
- Safety standards for sunglasses are mandatory in Australia but not in New Zealand. Do students think they should be mandatory in New Zealand? Why or why not? An open discussion of this second question might reveal aspects of students' underlying values in relation to regulation of public safety. Students who believe every person should be be responsible for their own decisions and actions may be less inclined to support mandatory safety standards.