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Science teachers make a huge difference to the education of their pupils. An inspired and engaging teacher will help any student to love science and follow it past secondary school, perhaps even into a degree. On the other hand, a dull teacher that over complicates everything and teaches at a snail's pace will bore the less able and patronize the more able. To be a successful teacher is not just about securing the highest marks possible from a class; it also requires a delicate teacher-pupil relationship to be formed from respect and trust in both sides. A teacher who scares away their pupils by not helping in a stressful situation, whether caused by not understanding work or other circumstances occurring in the classroom, will not help the teaching of science.

by Gary Dale (guest), 09 May 2013 17:44

As a comprehensive school Head of Science I offer my response to your article of 22 January ('Worthless qualifications' give false hope to state pupils).

Science is an intellectually challenging subject based on a coherent hierarchy of abstract conceptual models, mastery of which require a parallel development in mathematical ability. The Government has spent huge sums on a laudable campaign to increase state school students’ interest in becoming scientists and engineers whilst simultaneously distorting the curriculum to make it more ‘accessible’ and ‘relevant’ in ways that make it more, not less, difficult to learn enough science to follow it as a career.

Content has been steadily removed over the last few years in the name of accessibility. That which remains is largely chosen to illustrate wider ‘societal’ themes without sufficient regard to the theoretical coherence of the science being taught. For example: decisions about energy supplies – a bit of heat transfer, a bit of nuclear physics, a bit of transformers, a bit of atmospheric chemistry and a bit of ecology.

As assessment must not now seek to test understanding through mastery of mere Gradgrindian ‘facts’, we now have a system at age 11-14 which has replaced SAT exams with a typical piece of new Labour bureaucratic micromanagement, having 90 or so skills based performance statements. I was told at a recent training day that “it’s all about skills now; they can look up facts on Google”. Would you want to be treated by a doctor who has spent five years honing her evaluation skills instead of mastering those tedious old facts?

The IGCSE, which retains a coherent conceptual structure, cannot be offered in state schools as it “doesn’t conform to the Science Subject Criteria” (the very cause of the problem), whilst calls to offer IGCSE in state schools are denounced as “elitist”. The two tier system is returning to British education with a vengeance. Are we happy with independent school students learning about electromagnetic induction whilst their comprehensive peers have to grapple with assessment criteria such as “identify the use of evidence and creative thinking by scientists in the development of scientific ideas” when they have little clear idea of what those scientific ideas are?

University scientists, (as distinct from the culprits in the education departments), are belatedly showing signs of waking up to the situation, whilst the media and the wider political class, arguably dominated by Arts graduates, seem to remain blissfully unaware of the implications. Meanwhile, amidst signs of panic over UK students being overtaken in science and technology by their overseas competitors, the IGCSE is doing a roaring trade with…those very same competitors!


Andrew Urwin is Head of Science and Technology College Manager at a large state comprehensive in Devon. Prior to that he was Head of Physics at comprehensives in Sussex and Northumberland. He has been teaching for 20 years.

Precise or reliable?
"Any method of measuring that, when repeated, produces similar data over and over again is referred to as precise." in Edexcel 360, this is described as "reliable" evidence.

but my main concern is that we are giving pupils the impression that "being a scientist" is all about their ability to repoduce the meanings of words. The fact that the same word, or definition is used differently by different exam boards shows the futility of the execise.

so..at least an agreed and published working version for use in schools which all boards and books used would be helpful.

Re: Towards a sensible use of scientific terms from HSW by Mike Bell (guest), 23 Jan 2010 10:19

Is there any mileage in defining accurate values (at GCSE) as those with small errors in them?


Stuart Billington is a Head of Science in an 11-18 new Academy in the North West of England. He has 11 years of teaching experience.

I agree that this is very useful work.
I would just like to query one point - that is the idea of accuracy being defined as being relative to a known/accepted value.
This would be ok used in a historical sense, eg refering to Romer's value for the speed of light. Used about the present, I am not sure it has any use because there is no point in measuring "known" values unless the purpose is to refine/improve the known value. If you believe you have improved on the currently accepted value- the bigger the improvement made the lower the accuracy.
I think it (accuracy) has to be defined as being relative to the true value. Even though this makes the term almost redundant.
School science experiments are different - but is it wise to define terms for use in school science that are not then applicable elsewhere?

Re: Towards a sensible use of scientific terms from HSW by Peter Upton (guest), 20 Jan 2010 08:49

Stuart, excellent work. Perhaps we also need to think about how to teach these ideas to pupils that will be tested by papers using the language loosely, inconsistently and vaguely.
I have put my glossary thoughts at www.howscienceworks.org.uk/glosspage.html
Please feel free to make use of them or ignore them as you wish.

In September, I spent time pondering the term "precision". Since then, I have been considering some of the other HSW glossary terms also.

I understand that the ASE and the Nuffield Foundation have recently produced a book as guidance, but I don't think it proper that teachers should have to pay £10 to read about things demanded by an exam specification. I am afraid that I haven't read it — but would be very interested in the opinions of anyone who has.

Hopefully, the new exam specifications will include proper guidance/clarification, but, once more, I am deeply frustrated that such things will be foisted upon science teachers without any widespread canvassing of our opinion on the matter — especially after the debacle that we had to wade through last time.

So, here are my initial thoughts on some words that perhaps should be taught at GCSE as part of HSW. I would be most grateful for comments to correct mistakes, suggest improvements, make additions or suggest subtractions.

—-

Accuracy

In principle, accuracy describes the closeness of a measurement to the “true” value. However, as the “true” value is unknowable in practice, accuracy is more useful when thought of as closeness of a measurement to the “value currently accepted by the scientific community”. Even more usefully, “accurate” is a relative term – one measurement is more accurate than another if it has a smaller error.

Error

Anything that causes a measurement to not represent the true value is an error. Errors come in two categories – random and systematic.

Random errors are beyond the control of the experimenter and cannot be prevented (although they can often be reduced in size). Their effect is that sometimes the measured value with be slightly too high and sometimes slightly too low. Due to their random nature, random errors can be removed by taking the mean of many repeated measurements (as long as they agree). An example of random errors affecting a measurement is small variations in humidity, temperature or air movement affecting the rate of evaporation of water over short periods of time.

Systematic errors are artefacts of a flawed experimental method and are therefore, almost by definition, something that the experimenter is completely unaware of. The error will always be “in the same direction” (the measured value will either be consistently too high or consistently too low) and therefore averaging repeated measurements will not remove systematic errors from data. The best way to guard against systematic errors is to have someone else measure the same quantity and compare the two values, in the hope that they spot any oversights made. This cannot guarantee the elimination of systematic error but does increase the reliability of the measured value and conclusions based upon it. An example of systematic errors affecting a measurement is not removing shoes/standing straight/etc when measuring a person’s height.

Measurement precision

Any method of measuring that, when repeated, produces similar data over and over again is referred to as precise. Reducing random errors is the most straight-forward way of improving the precision of an experiment. Note, however, that systematic errors may still exist even in precise measurement methods and so precision has no bearing at all on accuracy. More precise experimental methods also result in greater reliability of measured values and conclusions based upon them.

The use of the word “precision” above, in the context of an experimental procedure, is unfortunate and confusing, as the word has an everyday meaning in the context of a single measured value. A single value is precise if it is quoted to many significant figures – ie it has a small uncertainty in its value (this has nothing to do with error). For example, 3.4m refers to an actual length between 3.35m and 3.45m. The uncertainty in the measurement is 0.1m. Compare this to the “more precise” value 3.42m, which limits the actual value to being between 3.415m and 3.425m, an uncertainty of just 0.01m. Improving the precision of measured values is most easily done by using more sensitive measuring devices – ie ones with finer scale divisions (higher resolution).

The two “precisions” are tenuously related — but must never be confused. To illustrate the loose connection, consider the fact that if individual measured values are precise (ie made with sensitive, high resolution measuring devices), smaller random errors will be more apparent and therefore greater efforts will have to be made to reduce them in order to achieve measurement precision. Precise values thus drive a push for a higher level of measurement precision.

The perfect experiment

Ideally, experimental methods will be constructed without systematic errors and steps will be taken to deal with random errors (for example, but not limited to, through the averaging of repeated measurements of the same value). Such methods will then be precise (return the same answers every time) and produce data that is both accurate (close to the true value) and reliable (unlikely to be wrong).


Stuart Billington is a Head of Science in an 11-18 new Academy in the North West of England. He has 11 years of teaching experience.

In my 25 years of classroom teaching I have found that students always respond with enthusiasm to being involved in project work either individually or in teams. The effect that that has in the students' attitude in the classroom is amazing. The important job for the teacher is to discover what are the particular interests of the student or group of students and devise a topic related to it for the students to work on. Whether students are involved in finding out by reading or by doing, they become much more aware of what is still out there to learn and that makes for a much more attentive and inquisitive student. After all that is what we want all our students to be.
Francisca Wheeler

We propose a dedicated unit for "being scientific" because, whilst we appreciate that many of these elements could be taught as part of an "embedded" scheme (as is the case with 21st C science etc.), we want to underline the importance of this material and ensure that it is not sidelined or thought of as "secondary". (Comment posted by Stuart, Mike and Alom)


Alom Shaha is a science teacher, writer, and film-maker

I loathe How Science Works. This is because it is a shabby excuse for something so important. It is truly deplorable that it's incarnation makes such a mockery of the underlying objectives. How Science Works should be consigned to history as quickly as possible (much like Windows Millenium Edition), to be replaced by what it should have been all along.

I think that HSW made a fundamental mistake — it combined (and therefore hopelessly confused) what Science is (as a monolithic enterprise spanning continents, peoples and centuries) with how an individual investigates in a Scientific manner. The former is so important, but has been lost in the haze of HSW. The latter are skills that should be embedded in any science curriculum as second nature to the science teacher — and yet HSW has reduced it to simplistic bolt-on activities with embarassingly naive and narrow assessments.

To illustrate this, below I have rearranged the HSW PoS statements. This is not in any way a vindication of the statements, but simply a way of highlighting my gripes.

The process of Science — What I'm calling "What is Science?", to be taught explicitly, separately to other content

  • how interpretation of data, using creative thought, provides evidence to test ideas and develop theories
  • that there are some questions that science cannot currently answer, and some that science cannot address
  • about the use of contemporary scientific and technological developments and their benefits, drawbacks and risks
  • to consider how and why decisions about science and technology are made, including those that raise ethical issues, and about the social, economic and environmental effects of such decisions
  • how uncertainties in scientific knowledge and scientific ideas change over time and about the role of the scientific community in validating these changes

Training students to become Scientists — what I'm referring to as "Scientific skills", to be taught implicitly as part of normal teaching activities

  • how scientific data can be collected and analysed
  • plan to test a scientific idea, answer a scientific question, or solve a scientific problem
  • collect data from primary or secondary sources, including using ICT sources and tools
  • work accurately and safely, individually and with others, when collecting first-hand data
  • evaluate methods of collection of data and consider their validity and reliability as evidence
  • use both qualitative and quantitative approaches
  • present information, develop an argument and draw a conclusion, using scientific, technical and mathematical language, conventions and symbols and ICT tools.

Superfluous and unnecessary statements

  • recall, analyse, interpret, apply and question scientific information or ideas
  • how explanations of many phenomena can be developed using scientific theories, models and ideas

I suggest that we move the skills to the Scientific Skills page and here, on this page, we focus on expanding and refining the five process of Science bullet points, developing ideas of how to deliver this explicitly in the curriculum.


Stuart Billington is a Head of Science in an 11-18 new Academy in the North West of England. He has 11 years of teaching experience.

Hi, DevonScience,

(Could you please alter your Screen name — both by going to My Profile? Thank you!)

Thanks for commenting!

See the next page in the process — 4. Principles. We don't know how to manage the divide, but we share your concerns and must find a way around it. We have some ideas, but have decided that we will have a better perspective on the issue once we have further developed the course.

Further, by structuring the curriculum over five years, we believe that there will be plenty of curriculum time for all routes, without timetabling more lessons in Y7-Y9.

Stu


Stuart Billington is a Head of Science in an 11-18 new Academy in the North West of England. He has 11 years of teaching experience.

by Stuart BillingtonStuart Billington, 01 Dec 2009 16:45

Could it be that pupils in year 8 may sometimes be too young know what they wish to do in the future?

It seems to me that creating such a vast curriculum divide in year 8 may determine their future prematurely, the 'proper science' course would require more timetabled lessons meaning those pupils could miss out on other aspects of their education.

In my short teaching career so far, I have had several very capable scientists at year 9 'opting out' from triple science so that they can choose other options…


Anthony Jackson. Teaching 3 years. An ecologist who is working as a physics specialist at present in Devon.

by DevonScienceDevonScience, 01 Dec 2009 16:21

Many thanks for your wise words, Rick. These are the reasons we have for 3 of the points you made.:

»'Recordbreaking results' in Successes and 'dumbing down' in Problems are in conflict.»

The first list of "sucesses" is a defence against the attack that we are being too negative. This is simply a list of some of the positive things people say about the new GCSEs eg "We have the best results ever". This is NOT in conflict with the facts of dumbing -down - ie, they got better reults either becuase the exams were easier or because the grade boubndaries were lower.

»I have a big problem also with 'logical order' »

This is not an attempt to tell teachers what to teach. The "logical order" is just for the concepts. It is based on the simple observation that some concepts need to be taught before others or the learner cannot learn. Eg lots of yr 10 pupils have trouble with chemistry because their concepts of atom, element, molecule etc. are not secure.

»what stage of learning we start teaching 'proper science' to those capable and willing to learn it. I would argue age 14 is appropriate»
we came up with starting in yr 8 partly because we know that the more able pupils are able and willing to learn "proper" science by then and partly because, when you list all the concepts they need to cover by the end of yr 11, there is not sufficient time in yrs 10 and 11.


Mike Bell, science teacher and trainer in evidence-based practice

Re: my tuppence by MikeBellMikeBell, 29 Nov 2009 11:10

I agree with both previous posters. With the loss of time, it is now no longer possible to teach science, then teach how to pass the exams. It is also easier to teach students how to pass the exams with much less actual science knowledge. In 2008 I gave up trying to do this, and prepared students who said they would take science no further solely for the exam. In HSW, my students got a 58% A/A* rate against 32% for my colleagues, all of whom I consider better teachers than me. My set 2 in year 10 got an average of 1 grade higher than set 1.
I now teach IGCSE abroad, and am emigrating.


Rick Hodge has 11 years in Independent secondary education, latterly as a Head of Science & Physics, and now teaches abroad.

The statements 'Recordbreaking results' in Successes and 'dumbing down' in Problems are in conflict. The GCSE results now show a 'C' grade in Physics written papers can be got for as little as 31%. I would argue, from speaking to friends in Industry and Business, that this of no practical use. The argument for or against the papers being easier is misleading. I would argue that the problems are (1) the removal of logical thought and mathematical difficulty in exchange for linguistic skills in interpreting questions, and (2) the lowering of pass percentages in the externally marked components. (1) is what means students are not prepared for further study, and also what puts off bright students. (2) is what means a low grade has no good purpose.
The courses have been revised in the order KS3,KS4,KS5. No wonder the Universities are unhappy!
We (scientists) need to make a decision as to what stage of learning we start teaching 'proper science' to those capable and willing to learn it. I would argue age 14 is appropriate, i.e. KS4. Naturally this means we also have to accept that 'one size cannot fit all'. By definition, GCSE Physics cannot be 'harder' than GCSE Core Science, which is why core science has to have half-life in it, which the less able don't understand, so they dumb the questions down, so it IS easier anyway(!).
I have a big problem also with 'logical order' and constant change. A good teacher should be able to structure a course to suit each class they have, which should ideally be done IN CONSULTATION WITH THE STUDENTS. A new good teacher (or teacher working out of specialism) should have sufficient material to "hang their hat on". This means there should be sufficient flexibility provided by the course and the department to do this. Constant changes make this impossible, as does modularisation. The teacher should then have sufficient time to tailor the material to their classes. I do not mean just lesson preparation, but course preparation.
Example from personal experience: new group of bright year 10 girls & a competition at Bristol University modelling earthquake resistant buildings. "Would you like to do this?", answer "Yes" (n.b. Set 3 said "no"). Tear up year 10 plan for this class and spend 4 months glueing sticks. V. busy teacher trying to make sure syllabus elements are included somehow. Results? girls come 2nd,3rd,4th & 6th, win £250 (cash! big party!). Of 18 girls, 2 girls become civil engineers, another does Geological Sciences at Oxford and another is now doing a PhD in geological fractures at Caltech. What a co-incidence! And all the others got the same grades in Physics as they did in the other 2 sciences. I don't understand the problem of students (especially girls) not doing STEM subjects; I've never had the slightest problem.
Problems with teaching. The root cause of all this is requiring teachers to teach outside their specialisation = little enthusiasm. If teachers wish to, fine; but you shouldn't oblige them to. Of course, you'd then have to pay the physical scientists more (at the moment). It doesn't matter that this is arguably 'unfair', because the rest of the world pays them more and you are in competition with them.
I think there is also a massive problem with too much context in syllabi, as it restricts the flexibility a good teacher has to tailor a course to their students. Bring back content! This is again just trying to cover up the problem of non-specialists, since specialists know enough context without an exam board having to tell them.

To summarise therefore:
Pupils 1 - Change must stop! The teachers will then have more time.

Pupils 2 Reduce the level of context and, together with 1, we won't need the material from the exam boards.

Pupils 3 Ban modularisation. Full stop. Then the course can be done in an order determined by each teacher & class. End of crazy non-links.

Pupils 4 This point and all the other 3, can be done by using IGCSE. I have taught very weak pupils and find any old science course at foundation level to be fine. You don't need to teach kids 3 sciences to educate them at KS4. They'll get scientific principles by studying any one of them, so let them pick one they like. Put the safety stuff like sunscreens in at KS3.

I'll stop now. Most of the other problems can be handled with what's above. Thanks for reading.


Rick Hodge has 11 years in Independent secondary education, latterly as a Head of Science & Physics, and now teaches abroad.

my tuppence by Rick HodgeRick Hodge, 28 Nov 2009 15:25

Polemic? Let's hope not; I agree with every word! :)


Stuart Billington is a Head of Science in an 11-18 new Academy in the North West of England. He has 11 years of teaching experience.

Re: Theories by Stuart BillingtonStuart Billington, 28 Nov 2009 14:42

I think somewhere we need to include that scientific theories can and do change as new evidence is discovered, and existing evidence is revised or discredited. I have always regarded science as essentially faithless; merely the best guess we have at the moment. It is also important, certainly for any students considering science at higher level, to point out where the weaknesses are in existing theories. That way we do not, as a body, look like a bunch of religious nutters or wizards&witches when theories come tumbling down. Recent discoveries in genetics showing that the Saxon and Norman invasions of Britain contributed less than 10% each to our current population has stood 300 years of "knowledge" on its head. Given the recent brohaha over the evidence for global warming also, we need to remember that the word theory does not necessarily mean 'wholly accepted', nor does it mean that it covers all the evidence. I trust this isn't too polemic for a first post.


Rick Hodge has 11 years in Independent secondary education, latterly as a Head of Science & Physics, and now teaches abroad.

Theories by Rick HodgeRick Hodge, 28 Nov 2009 14:12

Not just what we teach, but when we teach it and how we teach it. See Can-do tasks and OCR specification for details.

Andrew is right about the bite-size chunks being a problem, and the contrived language of "How Science Works".

Previous to 2006, when a topic builds then "teaching some of it well rather than all of it badly" was possible for students that struggled with higher level concepts, and you could gloss over some of the lower level concepts for high level students and spend more time on the things they found difficult. However, in the new GCSE you have lots of little chunks which restricts what you can do with the available curriculum time.


Helen Rogerson, Physics and Science teacher

My favourite example is electromagnetism. I want to teach it as part of a series of lessons so that my students don't just have to remember facts, but can UNDERSTAND it (or at least see patterns).

E.g. teach electromagnets and factors affecting them; teach the motor effect and factors affects (wow, they are very similar to last lesson Miss); teach them the generator (wow just the motor backwards Miss); teach them about transformers… (gosh now you are losing me Miss).

BUT we have to teach electromagnetic induction and transformers without actually teaching any of the physics. What is the point? Do we just hope that students can remember lists of facts for core science?


Helen Rogerson, Physics and Science teacher

I agree that science teachers, the people who know how children learn concepts because we teach them, should have a greater input to the science curriculum.

Do we want more A-C grades, or do we want a population with a good grasp of science content? I would suggest the latter, in which case can we teach waves before we teach "wireless communication"? Can we teach electrical current before we teach about solar cells? Can we have more than 2.5 hours to teach the whole of the digestion topic to our core GCSE classes?


Helen Rogerson, Physics and Science teacher

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