Archive for the ‘GCSE Standards’ Category

The Gravity Gnome

April 27, 2012
Weighing a Gnome

Weighing a gnome is actually a way of probing the gravity field around us.

Gravity is the most mysterious of the forces we experience in our lives. Impossible to screen against, it extends throughout space to the farthest corners (corners?) of the cosmos, causing every piece of matter in the Universe to affect every other. Wow!

More prosaically, gravity gives rise to the phenomenon of ‘weight’ – the force which pulls us ‘down’ to the Earth. GCSE students are tutored on the difference between mass and weight, and are told that the weight of an object, say a Gnome, varies from one planet to another, but its mass is the same on any planet. However, the Kern instrument company are keen to point out that if you use a sensitive force balance, its weight changes from place to place around the Earth.

The balance doesn’t even need to be that sensitive. I was surprised to find out by how much the weight of an object measured at a fixed height above sea level changes with latitude and longitude: – it varies by  around 0.5%. So for a Gnome weighing around 300 g, changes of 1.5 g should be seen and this is easily detectable. The rationale for the publicity stunt is explained here, and you can follow the Kern Gnome on his journey here. I like this experiment because the measurement is so simple – and yet the physics it uncovers is so profound.

The light-hearted video below shows my children’s reflections on the mystery of Gravity.

P.S. After a period of steady decline, my own weight has been mysteriously increasing. I think this may be due to a fluctuation in the gravitational constant G. More about this in future articles.

A level standards: A national disgrace

April 4, 2012
Scores on the Prior Knowledge Test (PKT) given to all students at the start of their B.Sc degree course at Bristol University physics department. Scores have systematically declined despite the amazing increase in apparent performance at A level

Scores on the Prior Knowledge Test (PKT) given to all students at the start of their B.Sc degree course at Bristol University Physics Department. The test has remained essentially unchanged, but scores have systematically declined despite the amazing increase in apparent performance at A level.

In 1985 around 9% of students obtained ‘A’ grades in their A-level exams. Since then, the percentage has increased every year and in 2010 the result was 27%. Is that because students are working harder and teachers are teaching smarter? Well, I can’t answer that question for every subject, but for physics the answer is an unequivocal ‘No’.

I can say this with certainty because the experience has been mournfully recounted to me by many teachers. And this month the anecdotal evidence was confirmed in an interesting paper by Professor Peter Barham published in Physics Education (download pdf here). Since 1975 the entire student intake to the physics course at Bristol University has taken essentially the same Prior Knowledge Test (PKT). Professor Barham published an analysis of these results and I have summarised one aspect of his analysis in the graph at the head of the page. It shows that scores testing prior knowledge of physics have declined by around 25% and are still falling.

Summarising, our national exam structure is reporting continuous improvement, but in reality students can achieve less and less. As I have commented previously, results such as this represent a national disgrace. This shameful situation is the product of:

Together these elements have combined to drive down educational standards. If this were a sport’s challenge these steps would involve:

  • Lowering the height of a ‘high jump test’ year upon year.
  • Stating that students could jump one metre when in fact they could only jump 25 centimetres, but they could do it 4 times.
  • The high jump inspectors guarantee the average height of the bar, but it is higher in some places and lower in others. The high jump inspectors publish guides explaining where the low points are.

In this case we can see that reports of continuous improvements in ‘high jump’ would be laughable. However, the educational system really matters. It is the way in which we pass on our combined cultural appreciation from generation to generation. And the confidence trick in which our educational establishment has conspired should make us angry.

However things appear to be changing. The modularisation of courses is slowly being undone. For his GCSE exams my second son will have to take all his science exams at the end of the course, a more difficult task than that which faced my first son. Michael Gove has now announced that in future A level ‘content’ will need to ‘involve’ academics at Universities. At this point it is impossible to foresee what this ‘involvement’ actually means, but it is probably a step in the right direction. However only when exam boards become fully independent of publishing companies do we stand a chance of reversing the continuous devaluation of educational qualifications.

School IT

March 14, 2012
Raspberry Pi

The Raspberry Pi computer. The machine costs £20 and is a fully-fledged computer. The user has to 'do' things and 'know' things in order to make it work!

Above all, education should empower children. And yet when it comes to Information Technology, IT, we are in danger of doing the opposite. Training courses such as the European Computer Driver’s Licence course show students how to use Microsoft’s ubiquitous ‘Office’ suite of applications and this is useful. So for example, learning to drive a car is useful: but it’s also not very difficult. And learning to use ‘Office’ applications is similarly, not very difficult.

In contrast, learning Newton’s laws, thermodynamics and materials science is hard, and you won’t actually be able to drive a car at the end of your training. But you will be able to understand, how a car works. And not just that: you might be able to imagine different types of cars, or even aeroplanes or rockets or submarines. Similarly, teaching computer programming will not directly help students to use a word processor. But they will understand how a word processor does what it does, and maybe they will even imagine new ways to use a computer. This is genuine empowerment. On this issue, if on few others, I am surprised to find myself agreeing with Michael Gove.

It is only when students take charge of computers that they become empowered, and I hope the Raspberry Pi computer will enable a resurgence in that. The Raspberry Pi is a fully-fledged but bare-bones computer costing around £20, and when it went on sale recently, it sold out in minutes. It was sold to people who are probably a bit like me. But my hope – and the hope of the Raspberry Pi foundation – is that it will find its way into the hands of children who will be excited by the prospect of making this device do what they want it to. In all probability this means using it to play games!

When my colleagues Gavin and Robin were teenagers the hottest technology available  was the Sinclair Spectrum, and a key attraction was the ability to create and play games! This ability fascinated them, and now – I think as a direct result of this early experience – they incorporate a profound understanding of programming into their skill set. Even now when any of us write software that works, and we control a machine or calculate the answer to a complicated problem, we all smile in appreciation at the technical sweetness of the process. In the case of my own programming achievements, Gavin and Robin smile mainly in sympathy 🙂

Being the age I am – 52 – it was not until I reached University that I met a computer. And I loved it! Using Commodore PET, a WANG, and an Apple II I learned the power of computing to set my imagination free. As an undergraduate  I calculated the orbits of planets in systems which Newton would have found impossible! Learning to program computers empowered and inpsired me.

One could take the view that a fascination with the minutiae of computing is as relevant today as a fascination with the details of a steam engine! ‘Chill out man‘ I hear some of you say, ‘Just consume media on your iPad and be grateful‘. I respectfully disagree. Empowering our children means enabling them to be creators, and not consumers, and computer programming is one the most creative of all activities.

Publishers should sell books – not exams.

December 10, 2011
An Exam

Is this (a) an examination or (b) a source of profit for Pearson publishing? Discuss

One of the challenges of bringing up teenage children is the task of relating one’s own educational experience to theirs. It’s hard, because things have changed so much. At the school attended by one of my children the teachers are obsessed with teaching children how to get marks in exams: it is an understandable obsession, but it is soul-destroying for children. IMHO teachers should teach children about their subject.  For all its faults – and there were many – my time at school was packed with ‘learning stuff’. Loads and loads of ‘stuff’! But that is not how things are in many schools these days.

The Telegraphs’s exposé of Edexcel’s practices – corrupt according to Steven Twigg MP – is damning. But this is not news to teachers.

During an Edexcel geography GCSE training course in Birmingham, the reporter asked Miss Warren why she should pick the exam board. Miss Warren replied, “It’s very, very traditional, Edexcel, and also, as these two will tell you [indicating to two teachers sitting nearby] you don’t have to teach a lot, do you?

No, there’s certainly a lot less content,” one teacher then said.

Miss Warren added: “Yes, in fact there’s so little we don’t know how we got it through [the exam regulators]. And I’m deadly serious about that. When I looked at it I thought, ‘how is this ever going to get through?’

As the teachers around Miss Warren agreed with her assessment of the Edexcel exam, she concluded: “It’s a lot less, it’s a lot smaller, and that’s why a lot of people came to us.

And the worm that has brought about these changes? The Telegraph pulls no punches:

Edexcel was previously a charity until it was acquired by Pearson, a multinational media company, in 2005. Its profits have since risen 10-fold and its managing director is one of the best-paid individuals in education. The company made profits of more than £60 million last year – compared with less than £5 million in 2003. A spokesman for Pearson said: “We do not see a conflict between our education goals and our commercial success. We believe they are mutually reinforcing. Our commitment to upholding standards and our ability to develop rigorous qualifications are fuelled by our financial performance.”

But sadly The Telegraph’s story -reported by the BBC as another morally corrupt scheme for teaching teachers how to get children to pass exams. – is no surprise. I have written about it before:

The solution is simple:

  • The UK needs one exam board which would be run by civil servants.
  • Exams should not be set, as they are now, by companies owned by large publishing corporations who will benefit financially if more students pass their exams.
  • Teachers should have no idea what will come up on the exam: they should teach ‘knowledge’ and then students who understand best will do best.
  • The definition of A and A* should be changed and defined not by the mark achieved but should indicate a percentile of the exam population. So for example an A* should indicate that a candidate is in (say) the top 1% of the exam group. An A would indicate (say) the top 5%. Marks B and C below this can be defined differently, and in this way grade inflation is avoided, but students who work hard can do better.

This is not rocket science – but we need to abandon the idea that ‘the market’ has any place in setting exams. Publishers should sell books – not exams. And certainly not set the exams and the books which will help students pass.

Sometimes…

October 14, 2011
Still from the Movie Rocket Science

Still from the Movie Rocket Science. Click the Image to link to the O2Learn Site

The Huffington Post report the news that Sharmila Hanson (aided and abetted by her husband Andrew) have won a staggering £150,000 in the O2Learn Film Competition! This is just great news, well deserved, and couldn’t have happened to a nicer couple. In this era of austerity and bad news, I was reminded of the poem Sometimes, by  Sheenagh Pugh which includes the lines:

Sometimes things don’t go, after all, from bad to worse.
Sometimes a man aims high, and all goes well.
Sometimes our best intentions do not go amiss.
Sometimes we do as we meant to.

The Sun will sometimes melt a field of sorrow
that seemed hard frozen; may it happen for you.

More depressing news about the shameful Exam Board scandal

November 8, 2010

News from the BBC confirming GCSE exam standards are indeed declining and shedding light of how it is being done. You can read the story here or download the podcast here. Basically the story is that the five Exam Boards compete to produce simpler exams that satisfy the ‘nominal’ benchmarks, but are easier to pass. As Mick Waters, the former head of QCA said ‘The system is diseased, almost corrupt’. Really depressing.

The story includes allegations that:

  • Exam boards ‘tipping off’ teachers about likely topics in exams.
  • OFQUAL are not investigating the professional malpractice around exams that boosts exam results.
  • There is a ‘race to the bottom’ in terms of exam standards.

My previous comments on the shameful phenomena are here. But without saying too much again, it is an outrage, that not-for-profit exam boards can be wholly owned by publishing corporations. IMHO the solution is simple: the UK needs exactly one exam board which should have no commercial involvement whatsoever.

Exam Standards: an apology is called for…

September 17, 2010

I was shocked to see a headline on the BBC web site today:

Exams system ‘diseased’ and ‘almost corrupt’

I was not shocked by the content of the headline, but by the fact that someone had managed to get such an opinion publicly expressed. You can read the BBC report here; the Guardian’s version here; and the Telegraph’s here. The story re-iterates several of the points I made in my letter to the Guardian last January. Briefly these are that the ‘competition’ between Exam Boards drives down standards, and the fact that the Exam Boards are wholly owned by publishers has comprised their independence. What is important about this story is not the obvious truth of the content, but the person who is saying it.

Mick Waters was until recently the Director of Curriculum at the Qualifications and Curriculum Authority (QCA). According to the BBC story, he didn’t believe any of the ‘dumbing down’ stories before he joined the QCA.

“You know, the old argument, more people passed than ever before. Since I’ve been there, I think the system is diseased, almost corrupt,”.

You can read the story for your self, but what I want to hear next is an apology. Our exam system is a profoundly important part of our culture – the formalised system by which we pass on knowledge from one generation to another. What has happened to our exam system is the equivalent of the sharp-dealing we have seen in the City: a kind of ‘get-clever-quick’ analogue to the ‘get-rich-quick’ schemes of the derivative traders. However, like their financial equivalents, the schemes only work on confidence. If confidence in qualifications is lost then they can become worthless overnight: I think we are close to that point now. And just as in a financial collapse it is not the derivatives traders that pay the price.

I don’t know who was responsible for this shameful episode. But somewhere there are people who oversaw this confidence trick and chose to say nothing. This quotation only became ‘News’ because somebody wants to sell a book and a good bit controversy is good publicity. But I don’t want to hear people’s excuses: I want to hear an apology.

What are ‘A’ levels for?

August 21, 2010
Percentage of students awarded A grade in A levels since 1965

The UK’s A level results came out this week and amongst all the opinions and emotions expressed I found the above graph profoundly significant. Essentially the whole ‘Exam Debate’ comes down to one simple question: Does this graph indicate a success, or a failure? Those who think it indicates a success attribute the rise to better teaching and those who think it indicates a failure attribute the rise to falling standards. I attribute the rise to what I call ‘wrong headedness’ – a complete inability to understand what A levels – and exams more widely – are for.

Before 1985, getting an A grade at A level meant that a student had  received an mark in the top 9% of results. In most subjects this mark was determined by performance in one or two exams taken at the end of a two year course of study. The purpose of the grading was to discriminate amongst the students. It offered teachers collectively no chance to improve. After 1985, everything changed and has kept changing ever since. The major shift was to a system where an A grade indicated a particular level of achievement. This offered the possibility that if teaching improved then more children would receive A grades. However changes in the style of exam, the modular exam system (which means that no one is ever tested on the whole syllabus) and the frankly appalling system in which the exam boards became wholly owned by publishers, means that a simple interpretation of the above as representing an improvement is not very convincing.

One role of our school system is to pass on the accumulated knowledge and understanding of our culture: this sounds rather pompous but it is true. It is hard to think of a more important task for any culture to undertake. The role of exams within this system is (very broadly) to check that this is being done. More specifically it needs to BOTH check that students know certain things by demonstrating a basic understanding AND to discriminate amongst the students and identify those with special talents or affinities. The above graph – and its seemingly unstoppable linear trend – indicates a collective failure to recognise the second purpose of exams.

Exam Standards: Good News and a suggestion

June 17, 2010

I have written here previously about my anger at the decline in exam standards, particularly at GCSE level and particularly in Science. And most particularly in Physics. My concern is that children from state schools which ‘teach to the exam’ will be denied the possibility of careers in Science. The Qualifications and Curriculum Development Authority oversaw a perncious system which systematically drove down exam standards year after year and penalised anyone – teachers, publishers or schools – who tried to object.

So it is great to report that the QCDA is moribund, and I am delighted to find that Ofqual has finally found the teeth to object to this decline. After rejecting the next syllabus revision as too low in standards today I read that they have sent back the exam boards revised syllabi as still not challenging enough. Hurray! Ideally, exam standards could rise year upon year as OfQual drove standards higher and higher. I am not hopeful, because the same political pressure which drove the previous government to devalue educational qualifications still exist. However I do have a suggestion.

My Suggestion

When I took my O level exams, the grade awarded was determined not by any absolute standard, but by where one came in the ranked exam order. Thus an A indicated that one had achieved a mark in the top 10% (say, I don’t know the exact fraction used) of the exam cohort. Nowadays an A indicates a mark exceeding 70% (I think) and can be achieved by any fraction of the exam cohort. It thus no longer serves to discriminate among exam candidates. And discrimination amongst candidates is – like it or not – a key purpose of exams.

If the old procedure was reintroduced it would automatically condemn a certain fraction of the cohort to ‘failure’, no matter what they achieved. However there is no need to use the system universally. A mixed system could be used: An A grade could still indicate the top 10%, B would indicate the next 10%, and C would indicate a norm-based pass above some nominal pass mark. There would be no limit to the number of people who could get C. This allows for improved teaching to result in improved pass rates without a guaranteed fraction ‘of failures’ while allowing employers or universities to look for academic high achievers.

  • Is there something wrong or unfair with this?

1975

March 18, 2010
The Jackson 5 in 1975

The Jackson 5 in 1975

Remember 1975? Possibly not, but I was reminded of the summer of that year recently when my good friend from school Richard Leahy sent me a pdf of the Physics_O_level_1975 (pdf). Please feel free to download the paper and have a go. There is no doubt that it requires a level of recall and facility with formulae and abstract manipulations that go way beyond GCSE. I don’t want to go on and on about this, but these days Richard is a fair old whizz with at all kinds of brain imaging. And he was set on this road to making peoples lives better by his education. He didn’t come from a family of academics and neither did I. I don’t have any doubt at all that if we had had the kind of education being offered in schools today, it would have been impossible for us to have achieved we have. The education we had stretched us and we are failing the capable children of today if we fail to stretch our children to achieve what they can.

Take a look at some of the things he can do at his site.


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