1. Teaching and learning about the nature of science:
Implications for physics teaching
Dr. Jim Ryder
School of Education
University of Leeds, UK

2. Outline What is the Nature of Science?
Why teaching/learning about the Nature of Science?
Students’ ideas about the Nature of Science/Physics
Implications for physics teaching

3. World Science The Nature of Science
A way of examining and talking about the world
The Nature of Science
Examining and talking about Science (‘Knowledge about Science’)

4. The Nature of Science
What are the purposes of scientific investigations?
How do scientists design investigations?
How do scientists assess the quality of data?
What is the nature of scientific explanations?
What are the limitations of science?
How does the scientific community work? (Internal sociology of science)
How do scientists/science knowledge interact with social issues? (External sociology of science)
Note Lederman et al. call to avoid confusing NOS with ‘processes of science’ (see handbook entry 2006). NOS might best be depicted as the ‘nature of scientific knowledge’? Hence NOS does not include Measuring Mass analysis of how to generate a ‘best estimate’ from a set of repeat measurements…
See my notes on this in research projects/nature of science-research notes

5. The scientific method? Observe phenomena Develop question
Create hypothesis
Design experiment
Conduct experiment
Analyse data
Draw conclusions
Based on:
Windschitl (2004) Folk theories of ‘inquiry’: How preservice teachers reproduce the discourse and practices of an atheoretical scientific method. Journal of Research in Science Teaching, 41(5), p
As often depicted in school text books
And reproduced in Winshitl study by a group of 14 pre-service secondary school science teachers, with science degrees.

6. The scientific method?
“There is no such thing as ‘the scientific method’. A scientist uses a great variety of exploratory strategems, and although a scientist has a certain (…) way of doing about things that is more likely to bring success than the gropings of an amateur – he uses no procedure of discovery that can be logically scripted.”
Medewar, P. (1984) The limits of science. Oxford University Press, p. 51.
Peter Medewar – English biologist, born 1915, shared nobel prize in medicine and physiology in 1960.

8. Objective observations?
Do we simply ‘observe’?
We use theories/ideas to interpret what we see
Standing on a hilltop at dawn two people are observing the eastern horizon.
One says: ‘the Sun is rising above the horizon and travelling up into the sky.
The other person says: ‘the Earth is turning, allowing us to see the Sun above the horizon’

9. Science Explanations
Science explanations are more than descriptions of phenomena/observations/data
DESCRIPTION
SCIENCE EXPLANATION
The Sun rises in the East
The Sun is at the centre of our Solar System. The Earth spins on its axis once every 24 hours.
A steaming hot cup of tea cools down
Evaporation produces cooling because the most energetic particles leave the liquid.
In a simple circuit the bulb will light up when the switch is closed.
When the switch is closed the charges in the wire form an electric current which transfers energy from the battery to the bulb.
Note more than one explanation can account for the data.
Explanations involves things you can’t see.
Abstract ideas.

10. Models of the atom Rutherford-Bohr for Neon
Probability density function (electron clouds) from Schrodinger wave equation.
Mathematical representation for counting electrons within electron shells – Oxygen.

11. Characteristics of explanations in science
Generalisable
particle theory of matter explains cooling through evaporation, solid-liquid-gas phase transitions, minimum temperature, expansion/contraction
Simplifying Assumptions
magnetic field lines in two dimensions; ignoring friction in dynamics; assuming a spherical Earth
Predictive Power
Particle theory of matter and minimum temperature; Bohr model of atom and chemical valency
Abstract ideas
Electron orbits, electron clouds; Mendel’s theory of inheritance and ‘genes’,
Use of analogies
Light moving as a ‘wave’ through the ‘aether’, Maxwell’s vortices
Mechanism
particle theory of matter provides a mechanism for expansion of solids on heating

12. The role of chance and status in the development of physics knowledge - the discovery of the electron spin
I think that you [Goudsmit] and Uhlenbeck have been very lucky to get your spinning electron published and talked about before Pauli heard of it. It appears that more than a year ago Kronig believed in the spinning electron and worked out something; the first person he showed it to was Pauli. Pauli ridiculed the whole thing so much that the first person became also the last and no one else heard anything of it.
Letter by L.H. Thomas to Goudsmit, 25 March 1926
Pauli
Samuel Goudsmit – Dutch physicist
George Uhlenbeck…– Dutch physicist
Both showed that Pauli’s forth quantum number could be explained by electron spin.
Ralph Kronig – German-American physicist
From Wikipedia: In January 1925, when Kronig was a still a Columbia University PhD student, he first proposed electron spin after hearing Pauli in Tübingen. Werner Heisenberg and Wolfgang Pauli immediately hated the idea. They had just ruled out all imaginable actions from quantum mechanics. Now Kronig was proposing to set the electron rotating in space. Pauli especially ridiculed the idea of spin, saying that "it is indeed very clever but of course has nothing to do with reality". Faced with such criticism, Kronig decided not to publish his theory and the idea of electron spin had to wait for others to take the credit. Ralph Kronig, had come up with the idea of electron spin several months before Uhlenbeck and Goudsmit. Most textbooks credit these two Dutch physicists with the discovery. Ralph Kronig did not hold a grudge against Pauli for this turn of events. In fact, Kronig and Pauli remained friends for many years into the future.
It is indeed very clever but of course has nothing to do with reality.
Pauli.

13. Outline What is the Nature of Science?
Why teaching/learning about the Nature of Science?
Students’ ideas about the Nature of Science/Physics
Implications for physics teaching
One answer would be: because it is interesting and enjoyable – i.e. like why we might want to learn about music, art… - Not because it has to be USEFUL….

14. The aims of scientific literacy 1
‘… much of the scientific knowledge acquired at school is forgotten by adulthood. Rather, what is needed is a much better understanding of the practices, processes and limits of scientific knowledge. Developing such an understanding is essential if individuals are to be able to make personal decisions and to participate in the public debate about the moral and ethical dilemmas increasingly posed by scientific advances …’

15. The aims of scientific literacy 2
‘…what is important is not that citizens should be able to remember and recall solely a large body of scientific facts, but that they should understand how science works and how it is based on the analysis and interpretation of evidence. Crucially, citizens should be able to use their understanding of science, so that science can help rather than scare them’.
Paragraph 86, House of Commons Science and Technology Committee (2002), Third Report of the Science and Technology Committee on Science Education from 14 to 19, (HC 508-I), (The Stationary Office, London).

16. Scientific literacy should not be taken to mean the knowledge of a lot of science, but rather the understanding of how science really works.
Durant, j. (1994) What is scientific literacy?, European Review, Scientific theories are guesses that haven’t been proved yet. After the theory is proven it will become a law. Vol. 2, no. 1,

17. Science and ‘real life’: Interactions with mobile phone technology
Science concepts: e.g. source-receiver model of radiation, non/ionising radiation…
Technology: use of network of base stations, directivity of the beam…
Nature of Science: the need for a large sample in studies, difficulty of designing studies over a long period of time outside of the laboratory.
For example, a prominent member of a mobile phone mast protest group recognised that there was a great deal of uncertainty about the possible longer-term non-thermal effects of mobile phone use, given the long time horizons involved, and the complexities involved in undertaking such studies (Drake, 2006). Such an insight requires understandings about how science investigations are conducted in complex contexts outside of the laboratory. Burgess describes the case of a parent who was convinced that moving her child away from a school sited near to a mobile phone mast was the cause of a dramatic improvement in her child’s health: ‘she’s a different child now – it’s all the proof I need to convince me there is a link between those wretched masts and the health of children’ (Burgess, 2004, p. 1). This individual is using a single case linking two factors as a necessary indication of a causal link.
(From Hodson Handbook chapter)

18. Science and ‘real life’: Interactions with mobile phone technology
The case of a parent who was convinced that moving her child away from a school sited near to a mobile phone mast was the cause of a dramatic improvement in her child’s health:
‘she’s a different child now – it’s all the proof I need to convince me there is a link between those wretched masts and the health of children’
(Burgess, 2004, p. 1).
For example, a prominent member of a mobile phone mast protest group recognised that there was a great deal of uncertainty about the possible longer-term non-thermal effects of mobile phone use, given the long time horizons involved, and the complexities involved in undertaking such studies (Drake, 2006). Such an insight requires understandings about how science investigations are conducted in complex contexts outside of the laboratory. Burgess describes the case of a parent who was convinced that moving her child away from a school sited near to a mobile phone mast was the cause of a dramatic improvement in her child’s health: ‘she’s a different child now – it’s all the proof I need to convince me there is a link between those wretched masts and the health of children’ (Burgess, 2004, p. 1). This individual is using a single case linking two factors as a necessary indication of a causal link.
(From Hodson Handbook chapter)

19. Science in a Public Domain
School Science
Established knowledge
Hard facts
Ready Made Science (Latour)
Science in a Public Domain
Contested knowledge
Complex, ‘real world’ contexts
Science in the Making

20. Outline What is the Nature of Science?
Why teaching/learning about the Nature of Science?
Students’ ideas about the Nature of Science/Physics
Implications for physics teaching
Handout students’ ideas about nature of science quotes.
In pairs, Do you agree with the student? If not, why not…

21. Scientists are independent of government.
In an experiment you should keep taking measurements until you get two values that are the same. That’s then the true value.
If two scientists disagree about the interpretation of data from an investigation then one (or both!) of them must be incompetent or biased.
Scientists are independent of government.
Scientists should be able to tell us whether something is completely safe (e.g. using mobile phones).
Review:
1) this is a view that comes from school practices…
Suggest they try using these as prompts for discussion with their pupils.
(3) always promotes good discussion
(4) they are often more thoughtful about risk than we give them credit for – some still expect clear proponucements: it’s safe… (e.g. mobile phones, MMR vaccine…)

22. Young people’s ideas about theories in science
‘If you set up a hypothesis not yet clearly proven, it is a theory. After the theory is proven it will become a law’
‘It’s just a theory – they don’t know for sure’
‘Theories are guesses that haven’t been proven yet’
Kang, S., Scharmann, L. C., & Noh, T. (2004). Examining students' views on the nature of science: Results from korean 6th, 8th and 10th graders. Science Education, 89,
Kang found of Y10 Korean students (sample 617) using written questionnaire:
20% chose an option suggesting guesses yet to be proved,
50% a fact proven by many experiments
– only 26% suggested theories as an explanation of how things happen.

23. Students’ understandings of the nature of scientific knowledge I
Level 1
Knowledge directly reflects reality.
The goal of science is to invent things.
Lack of distinction between the goal of understanding a phenomenon and producing a phenomenon.
Lack of distinction between theory and evidence.
‘An experiment is when you try it and see if it works’
The goal of science is:
‘to discover new things’;
‘to find new cures for diseases’
Study involved 27 students age 12 in Boston, US.
Pre/post instruction design.
Before/after a 3 week long teaching unit about the nature of science.
Clinical interview probe.
Typical levels of these students 1-2, with very few at 3, and this improved with instruction.
In more detail: mean overall score before teaching was 1.0,
- Mean overall score after teaching was 1.6.
Levels used with older pupils (see Smith and Wenk 2006):
35 college Freshmen, various across arts/sciences, using i/vs
level 2 most common
- level 3 ‘virtually non-existent’
- see Table 1, p751 in that publication.
Carey, S., Evans, R., Honda, M., Jay, E., & Unger, C. (1989). 'an experiment is when you try and see if it works': A study of grade 7 students' understanding of the construction of scientific knowledge. International Journal of Science Education, 11,

24. Students’ understandings of the nature of scientific knowledge II
Level 2
Clear distinction between ideas and experiments.
Inquiry is guided by particular ideas and questions.
No recognition that the results of an experiment may lead to revision of an idea.
Scientists do experiments : ‘to test to see if their idea is right’
Study involved 27 students age 12 in Boston, US.
Pre/post instruction design.
Before/after a 3 week long teaching unit about the nature of science.
Clinical interview probe.
Typical levels of these students 1-2, with very few at 3, and this improved with instruction.
In more detail: mean overall score before teaching was 1.0,
- Mean overall score after teaching was 1.6.
Levels used with older pupils (see Smith and Wenk 2006):
35 college Freshmen, various across arts/sciences, using i/vs
level 2 most common
- level 3 ‘virtually non-existent’
- see Table 1, p751 in that publication.

25. Students’ understandings of the nature of scientific knowledge III
Level 3
The purpose of experiments is to test and explore ideas - if unexpected results appear the scientist will need to modify their idea.
Science is a cyclic, cumulative activity.
A scientist: ‘probably thinks up an idea, and then builds an experiment out of the idea, and if he’s right or wrong he keeps building up more questions to see, to find out even more stuff than he knows’
‘He’d probably have to change his hypothesis a little to fit in with the new data’
Study involved 27 students age 12 in Boston, US.
Pre/post instruction design.
Before/after a 3 week long teaching unit about the nature of science.
Clinical interview probe.
Typical levels of these students 1-2, with very few at 3, and this improved with instruction.
In more detail: mean overall score before teaching was 1.0,
- Mean overall score after teaching was 1.6.
Levels used with older pupils (see Smith and Wenk 2006):
35 college Freshmen, various across arts/sciences, using i/vs
level 2 most common
- level 3 ‘virtually non-existent’
- see Table 1, p751 in that publication.

26. No differentiation of ideas and evidence
Level
Key differentiations
Nature of knowledge
Process of enquiry 1
No differentiation of ideas and evidence
True beliefs about what happens and what works
Making observations, doing tests, finding answers 2
Simple differentiation of ideas and evidence
Well tested hypotheses; generalisations about how or why something works
Simple hypothesis testing 3
Differentiation among theories, hypotheses and evidence
Well tested coherent theories (explanatory frameworks)
Cycles of hypothesis testing that test and develop theories
Study involved 27 students age 12 in Boston, US.
Pre/post instruction design.
Before/after a 3 week long teaching unit about the nature of science.
Clinical interview probe.
Typical levels of these students 1-2, with very few at 3, and this improved with instruction.
In more detail: mean overall score before teaching was 1.0,
- Mean overall score after teaching was 1.6.
Levels used with older pupils (see Smith and Wenk 2006):
35 college Freshmen, various across arts/sciences, using i/vs
level 2 most common
- level 3 ‘virtually non-existent’
- see Table 1, p751 in that publication.
(Based on Carey and Wenk, 2006)

27. Student conceptions of knowledge generation and justification in science
Experimentation
Students often view experiments as a method of trying things out or producing a desired outcome, rather than a method of testing ideas.
Models
Many students think of models as physical copies of reality, rather than as conceptual representations.
Interpretation of data
Students show a tendency to infer cause from correlations, or even a single co-occurrence.
So, given these ideas, what’s the problem? Return to Mobile Phones Study…
Inadequacies in arguments
Many students accept arguments based on inadequate sample size or statistically insignificant differences.
After: Donovan, M. S., & Brandsford, J. D. (Eds.). (2005). How students learn: Science in the classroom. Washington DC: The National Academies Press. Box 9.1, p. 402.

28. Outline What is the Nature of Science?
Why teaching/learning about the Nature of Science?
Students’ ideas about the Nature of Science/Physics
Implications for physics teaching

29. 21st Century Science GCSE Course
We need a curriculum model for science that offers flexibility and genuine choice to cope with the diversity of students' interests and aspirations.
The model we propose offers all students the chance to develop the scientific literacy that they need to play a full part in a modern democratic society where science and technology play a key role in shaping our lives - as active and informed citizens. In addition, for some students – perhaps a minority – we are producing courses which provide the first stages of their training as a scientist, or for a career that involves science.

30. Curriculum purposes
Science education as preparation for advanced study in science
Science education to support people’s engagement with science as citizens

31. 21st Century Science
Twenty First Century Science offers three different GCSE science courses for different purposes.
Science: scientific literacy for all
For all Key Stage 4 students (age 14 to 16), taking 10% of their curriculum time and leading to one GCSE grade.
Additional science
Alongside core Science, young people can opt for one of two Additional Science courses, also taking 10% of curriculum time and leading to one GCSE grade:
- Additional Science
- Additional Applied

32. 21st Century Science GCSE Course
Module topics (e.g. Air Quality, Keeping Healthy, Food Matters)
Scientific Explanations
Ideas about Science (i.e. the ‘nature of science’)

33. A protest from those that see this curriculum as being ‘dumbed down’; a lowering of standards - an attack by leading academics on the 21st CS course…
‘There is no physics in it’…
Poor preparation for advanced study
A back to front approach: ‘science should inform the new agenda, not the other way around’
There is a battle going on for the core of science curriculum for all – at least in UK… how will this impact of students…?

34. Teachers’ experiences of 21CS
We notice that the enthusiasm, the engagement level is going up, so they’re becoming more interested in science. We are having pupils who are staying behind to ask questions in certain groups which wasn’t happening before
Well with our kids in particular, they love discussion and (…) they are very good at doing it. What I would think our teachers need is strategies on how to actually do discussions (…) a lot of teachers are too scared to kind of let go and just let the kids talk about stuff, and then sort of bring them back together to find out what they think.

35. Teachers’ experiences of 21CS
There are two things that have happened this year that have not happened before. The first thing is that lessons have been completely taken over by the students asking the questions. The second, and by far the best, thing is that not once, not on a single occasion, not ever this year have I had to answer the question ‘why do we have to learn this?’
(Teacher quoted in IOP Education newsletter Feb 2008)

36. Teachers’ experiences of 21CS
Should Physics be more elitist?
Physics is a subject that requires certain intellectual skills that the majority of the population do not have… there persists a strange notion that anyone and everyone should study… physics … such a notion is patently absurd.
(Headteacher, Physics World, 2004, in an exchange with Jonathan Osbourne)

37. Leeds study 38% improved student motivation
240 teachers; written questionnaire; open responses
End of first run through 2 year courses for year olds
38% improved student motivation
30% improved student achievement
45% challenge of managing changes to assessment
29% difficulties with resourcing
14% difficulties with teaching nature of science
12% difficulties ‘finding’ practical work
19% ‘dumbing down’ of science curriculum
CONFIDENTIAL _ FROM QCA STUDY.

38. Students’ experiences of 21CS
It is a quite up to date modern course that teaches you useful things that you can relate to like real life situations, so you could actually use it in real life.
You remember more out of these lessons because it is more relevant to you now, instead of just you go past and see a sign for like genetic babies and you would say ‘oh I know about that’

39. Challenges and opportunities ahead
The curriculum is already overcrowded. How can we possibly teach more in the science curriculum?
Why change the science curriculum yet again?
All this is new to me. How do I teach the nature of science?
I enjoy teaching about the nature of science but many of my students resent it because it isn't on the exam.
All this ‘discussion’ about socio-scientific issues is going to ‘turn off’ the students who would normally choose to study physics further, and become the physicists of the future