Physics subject plan online

We had a Physics inspection last year which involved putting together a Subject plan (not that it didn’t exist previously of course, but you know what I mean). It did take quite a bit of time and it occurred to me that, given that most schools in the country offer Physics as a subject, it would make sense to those who have yet to create their own to see one which is already in existence.
It is of course not the definitive article but nevertheless should prove particulary useful to both new teachers and those who have been ‘drafted in’ from other subjects to teach Physics.

Feel free to incorporate as much or as little of it as you like; if I make any major changes I will let you know via the blog or twitter.

The plan itself can be accessed directly from here or from the homepage of thephysicsteacher.ie

Feel free to offer constructive critisism 🙂

I hope to get around to producing something similar for Applied Maths at a later stage.

Wouldn’t it be nice if every department in every school had to put their subject plans online – I’m sure it would be appreciated by parents who are looking to decide what school to send their children to.

If I were a schools’ inspector I would look for evidence of the following:
  • The teacher reflects on their teaching.
  • The teacher has got their own Personal Learning Network and engages with it.
  • The teacher tries to introduce some new initiave or strategy into their teaching every year, and then tries to evaluate its success or failure.
  • The teacher encourages (constructive) feedback from all quarters.
  • The teacher is not teaching in a style that is somewhere between 400 and 4000 years old.
  • The teacher is familiar with Differentiated Learning and Assessment for Learning and has some initial strategies for incorporating both of these into lesson plans.
    In relation to Differentiated Learning the teaching strategies should aim to cater for both those with learning difficulties and those who need further higher-order thinking activites.

Hopefully I won’t get inspected by one of these inspectors anytime soon.

We are star-stuff: teaching about the elements

We had fun with these resources yesterday so I thought I would share them.

First up, where did all the stuff that makes up you and me come from?

Hold up your hand: You are looking at stardust made flesh. The iron in your blood, the calcium in your bones, the oxygen that fills your lungs each time you take a breath – all were baked in the fiery ovens deep within stars and blown into space when those stars grew old and perished. Each one of us was quite literally made in heaven. Modern science has shown us that we are more intimately connected to the stars than anyone dared to guess.”

The author of this magical piece, as far as I establish, is Marcus Chown, but if anyobdy can confirm or correct I would appreciate it.

I have this taped to the outside of my lab door, and was delighted to see a first-year take it down into her notebook recently (not sure the senior years ever stop to even notice it, but maybe that says more about our education than anything else).

It turns out that pretty much all the hydrogen in and around us is here from the time of the Big Bang over 13 billion years ago, and most of the helium is also that old (although helium is still being created all around us in the form of nuclear radiation). These are the first two elements in the periodic table. These eventually formed stars and in the process (nuclear fusion) formed the next 24 elements (up to iron). But even the energies involved in the sun’s day-to-day activites aren’t great enough to produce elements heavier than iron. So where did all the other 90 elements come from? (and remember that all these elements are what you and I are made from today).

Eventually the fuel (and energy) to produce fusion runs out and thus begings the final steps of a star’s incredible journey. But even in death they have a sting. Most ‘dead’ stars don’t just sit there, no sirree bob. The phrase ” it’s better to burn out than fade away” cannot be more apt than when applied to the death knell of one of these incredible stellar objects. If the star has enough mass then after collapsing in on itself it ‘rebounds’ and sends out the mother of all shock waves, one which is so strong that it actually tears the sun itself apart – it has become a ‘supernova’. A supernova explosion can be as bright as 4 billion (yes billion) suns. Not surprisingly it can become the brightest thing in the night sky for days (the last documented one within out own galaxy seeems to have been in 1604, but the Chinese also had written about one a thousand years before that).  Not that the 1604 explosion actually happened in 1604; it actually happened 13,000 years previously – it just took that long for the light to get from there to here (‘there’ and ‘here’ also being relative terms). But I digress.

When the star explodes the energy it contains is now sufficient to create all the heavier elements above iron, from copper upwards.

So there you have it: we are stardust.

The Amerian physicist Neil de Grasse Tyson sums it up rather nicely:

The gentleman you saw briefly in the background is Carl Sagan

Sagan was like Richard Dawkins without the arrogance, indeed he was a much more successful communicator  because he delibertately chose to preach not just to the converted, but to all. He would not have been impressed with Dawkins:

People are not stupid. They believe things for reasons. The last way for skeptics to get the attention of bright, curious, intelligent people is to belittle or condescend or to show arrogance toward their beliefs.

Here is Sagan taking us on a whirlwind tour of the history of our planetary and biological evolution.

But of course there’s no chance that any of the good stuff here will ever appear on a syllabus near you.
It’s also pretty unlikely that, with the exception of Humphrey Jones over at the frogblog, many other science teachers get animated by this. It seems to be the humanities teachers who are more likely to tackle the mystery and wonder of science. I guess those teachers who are fascinated by the wonder in Science are happy enough to enthuse their own students and leave it at that.
For another day perhaps.

And now for something completely different:

Science really does seem to be coming back into fashion – no longer is it just for the nerds. Or maybe it still is for nerds, but nerds are now cool. Thank you Stephen Fry.
Here’s Daniel Radcliff’s version:

Finally, for something a little more light. And for bonus points, for what sitcom do this band have an even more catchy tune?

Naming of Parts, by Henry Reed
One poem that I particularly like (and have hanging outside the door of my lab) is “Naming of Parts” by Henry Reed; it contrasts a lesson in military weaoons with a flowering plant.
My classroom looks out on a flower garden and I often think of this poem as I spot another student gazing wistfully out the window as I waffle on about the finer points of electromagnetic induction.

Naming of Parts

Today we have naming of parts. Yesterday,
We had daily cleaning. And tomorrow morning,
We shall have what to do after firing. But today,
Today we have naming of parts. Japonica
Glistens like coral in all of the neighboring gardens,
And today we have naming of parts.

This is the lower sling swivel. And this
Is the upper sling swivel, whose use you will see,
When you are given your slings. And this is the piling swivel,
Which in your case you have not got. The branches
Hold in the gardens their silent, eloquent gestures,
Which in our case we have not got.

This is the safety-catch, which is always released
With an easy flick of the thumb. And please do not let me
See anyone using his finger. You can do it quite easy
If you have any strength in your thumb. The blossoms
Are fragile and motionless, never letting anyone see
Any of them using their finger.

And this you can see is the bolt. The purpose of this
Is to open the breech, as you see. We can slide it
Rapidly backwards and forwards: we call this
Easing the spring. And rapidly backwards and forwards
The early bees are assaulting and fumbling the flowers
They call it easing the Spring.

They call it easing the Spring: it is perfectly easy
If you have any strength in your thumb: like the bolt,
And the breech, and the cocking-piece, and the point of balance,
Which in our case we have not got; and the almond-blossom
Silent in all of the gardens and the bees going backwards and forwards,
For today we have naming of parts.

I posted this on a Physics teachers’ forum a number of years back and one reader was so impressed by the poem that she immediately adapted it to her own lesson. I obviously wasn’t the only admirer of her work – the adapted poem appeared in the journal “Physics Education” shortly afterwards. I haved included it here with the kind permission of the author.

Induced emf

Phoebe Wales

To-day we have induced emf. Yesterday,
We had motor effect. And to-morrow morning,
We shall have eddy current braking. But to-day,
To-day we have induced emf. Japonica
Glistens like coral in all of the neighbouring gardens,
And to-day we induced emf.

This is the flux density. And this
Is the flux, whose use you will see,
When you differentiate it with respect to time. And this is the cosine of the angle,
Which in your case you don’t need to do. The branches
Hold in the gardens their silent, eloquent gestures,
Which in your case you don’t need to do.

This is Lenz’s law, which is just an addition
To what Faraday had already said. And please do not let me see
Anyone using the wrong units. You can derive them quite easily
from SI units. The blossoms
Are fragile and motionless, never letting anyone see them
Using the wrong units.

And this you can see is how quickly flux changes. The purpose of this
Is to calculate the emf. We can apply it
To an isolated wire: this creates
A pd between terminals. And rapidly backwards and forwards
The early bees are assaulting and fumbling the flowers:
A pd between terminals.

They call it Fleming’s right hand rule: it is perfectly easy
If you have any spatial awareness: take your right thumb,
And first finger, and second finger, and the directions they point,
Clearly give you the answer; and the almond-blossom
Silent in all of the gardens and the bees going backwards and forwards,
For to-day we have induced emf.

The Two Cultures – why our schools are to blame

When I Heard the Learn’d Astronomer

By Walt Whitman

When I heard the learn’d astronomer,
When the proofs, the figures, were ranged in columns before me,
When I was shown the charts and diagrams, to add, divide, and measure them,
When I sitting heard the astronomer where he lectured with much applause in the lecture-room,
How soon unaccountable I became tired and sick,
Till rising and gliding out I wander’d off by myself,
In the mystical moist night-air, and from time to time,
Look’d up in perfect silence at the stars.
Scientists often complain about how they are perceived in literature. It seems as though the battle – with writers, poets and artists on one side, and scientists on the  other – has been going stong long before C.P. Snow wrote about ‘The Two Cultures’ back in 1959.
It was a strong theme all through the Romantic era and more recently prompted Richard Dawkins to write an entire book on the subject.  His take on it was similar to that of Richard Feynman; far from taking from the wonder of the subject, science actually adds to it. We can still appreciate the beauty of nature while having a deeper understanding of the reason nature is the way she is. Dawkins’ booktitle was a reference to a Keats poem about the wonder of rainbows, but it’s not an uncommon complaint; Richard Feynman says something similar about a simple flower.

What I find fascinating is that neither Feynman or Dawkins (or indeed C.P. Snow himself) seem to wonder why many artists have such a poor view of science. Walt Whitman’s poem above seems to be a fair reflection of how scientists in general are viewed by  the public at large.

For me, this poor image of Science (and scientists) is generated in school. The textbooks are terrible, the syllabus even more so, and it is only the enthusiasm of the odd teacher that creates any sort of positive image of the subject. It seems to me that science teachers at secondary level and lecturers at third level do very little to inspire wonder in any student who isn’t already fascinated by the subject. I have said it on many occasions before; when you consider the enthusiasm of students for the subject when they first encounter it in first year, and contrast this with their weariness for the subject in sixth year, it’s a wonder any of them choose to keep it on at third level. Of course the pigeon-holing of all knowledge into outdated compartments called ‘Subjects’ may also have something to do with this.

And unfortunately all the Science Weeks and Science Gallaries and Cities of Science in the world won’t change this.

What might result in change is if more attention was paid to our abysmal syllabus by some of these folk who are so heavily involved in promotion of science ourside the classroom; perhaps if enough artists and writers addressed this issue . . . a new romantic movement anyone?

Thanks to my colleague Mr Devitt for reminding me of the Walt Whitman poem. Young Devitt is one of those indivuals who is as happy talking Physics/Science as he is talking History (his trade). I am fortunate in my school to have a number of such colleagues, but as with teachers  everywhere else there is just so little time or opportunity to allow for cross-pollination of this sort. What I find fascinating about discussions with colleagues from the humanities side of the fence is that they always seem to have more of a sense of wonder for the (science) ideas than do my science-teacher colleagues. I don’t know why that is.

Teachersource.com – for all your Science toys/Xmas pressies


If you haven’t yet bought your Christmas pressies, you could do a lot worse than consider teachersource.com as your one-stop shop.

I have been using it for years; it’s a fantastic source for science ‘toys’ for your lab, but there’s no reason why you couldn’t use it to stock up on presents for the little ones in your life – ideally they won’t have started secondary school yet so will still be fascinated by Science.
In fact this year I pointed the site out to my first and second-years and they have actually used it themselves to order presents. And it’s all Science!
Their two hottest items are the fun fly-stick and this, their most recent item – the air swimmer

One tip: if you opt for the express delivery (via UPS) it’s not only more expensive but you will also be caught for customs duty. Beware!

Then Jesus took his disciples up the mountain and gathered them around him

Think I may have posted this before, but I was reminded of it by a colleague again recently – it’s an oldie but a goodie:

Then Jesus took his disciples up the mountain and gathered them around him

He taught them saying:
“Blessed are the poor in spirit for theirs is the kingdom of God.
Blessed are the meek.
Blessed are they that mourn.
Blessed are the merciful.
Blessed are they that thirst for justice.
Blessed are you when you are persecuted.
Blessed are you when you when you suffer.
Be glad and rejoice for your reward is great in heaven.”

And James said “are we supposed to know this?”
And Simon Peter said “will we have a test on this?”
And Phillip said “I don’t have any paper.”
And Bartholomew said “do we have to spell correctly?”
And Mark said “do we have to hand this in?”
And John said “the other disciples didn’t have to learn this.”
And Matthew said “may I go to the toilet?”

Then one of the Pharisees who was present asked to see Jesus’ lesson plan
and inquired of Jesus:
“Where are your learning and assessment objectives?
What range of teaching strategies did you draw from?
Did you provide a differentiated provision?
Can I see a cross section of pupils work?

And Jesus wept.

We need to take responsibility for our own professional development

It may seem hard to believe but most second level teachers in this country have never seen another colleague teach their subject other than the teacher they had themselves as a student and possibly a few class observations when they were doing the hDip. Neither is there currently any obligation on us to initiate communication with colleagues in other schools either within the country or elsewhere.

This needs to change. Few if any of us are so expert in our teaching that we have nothing left to learn. In the past establishing a space for this learning to occur was the main stumbling block but now with the advent of technology there is no such excuse. The experts call it a PLN – a professional learning network – and it should revolutionise education. It works like this: sign up to twitter and start following someone (anyone – it doesn’t matter who; @thefrogblog wouldn’t be a bad starting point). Very quickly you will start receiving tweets and links from other teachers. You can then choose to ‘unfollow’ those who don’t appeal to you. It’s a very fluid process and in the main people don’t mind (or probably even know) if you unfollow them so don’t think you are signing up to some lifelong commitment. It’s quite likely you will chance upon a number of people who you know personally but didn’t realise were on Twitter.

Slowly you will begin to establish a list of people who you rate highly – you are now developing a PLN. You are in complete control and with time should come the confidence to contribute yourself. It’s only then that you realise the potential. Personally I find the posts of physics teacher @fnoschese to be of greatest benefit but that could all change tomorrow if my interests take a different turn.

I imagine many teachers have developed a PLN without ever realising what it was called and chances are that in the past it was through personal communication via a subject organisation like the ISTA. Probably the greatest assistance to my professional development over the years was a discussion group for teachers of physics in Britain and Ireland as part of the Institute of Physics. It was a place where I could post any problems that I had in either understanding a concept or indeed explaining the concept to students. But its greatest feature was in reading the comments that other teachers wrote which made me realise that concepts which I thought I understood were completely wrong and in many instances were perfect examples of the type of misconception which I was trying to eradicate in my own students’ heads.

The amount of time I was able to give to this varied enormously but now with the advent of Twitter and the smartphone all of this information is literally at the touch of a button.

One consequence of all this however is to make me realise that my style of teaching is highly questionable from a pedagogical point of view. It might be all bells and whistles, the students may love it and I get a great sense of satisfaction from it, but all the research shows that this traditional model is pretty ineffective. Frank Nochese (mentioned above) refers to it as ‘pseudoteaching’ and I like to turn that around and suggest that what my students are doing in the main is ‘pseudolearning’; I think they’re learning, they think they’re learning and the exam results are keeping everybody happy, but it only takes a little prodding to realise that much of this learning is superficial – concepts are not really understood, they are merely ‘learned off by heart’. And that’s not good enough. The use of assessment as a learning tool instead of its current function which is simply to assign grades is another example of how I have fallen behind as a professional.But that’s for another day.

The point is, whatever we call it, we all need to be in constant communication with colleagues. We all need to give and receive feedback. We all need to strive to improve.

Currently there is little external incentive to develop a PLN, neither are there any penalties for not doing so, but one would hope that it is only a matter of time before this changes. Watch this space.

Energy – the most poorly-taught concept in all of science?

It is important to realize that in physics today, we have no knowledge what energy is.

Richard Feynman

Sometimes when I’m teaching I have been known to go off on a tangent which may be only marginally related to what we’re doing in class; other times I manage to restrain myself and may just allude to the tangential concept in passing.

But then there are times when these tangents are actually necessary, and by leaving them out I am doing the students an injustice. Ususally I try to include this information in the students’ notes also but sometimes I just don’t get around to it. Energy is just such an example.

Georgina (this is where I’m supposed to say that Georgina is not her real name, but as far as I’m aware it actually is) is one of the top students in my fifth year class this year and I used to think that she was a bit of a ‘slogger’ – liked to work hard and liked to know that there was always a ‘correct’ answer. In fact I wasn’t even sure if she would adapt to my style of teaching, where I tend to ask questions and not always provide the answers. But Georgina showed what she was really make of when we were revising the chapter on Energy.

“I know this sounds like a silly question”, she said, “and I know we’re finished the topic now, and it’s not that I can’t do the problems and exam questions because I can, it’s just that I don’t seem to get what energy actually is”

I realised that there was more to this student than I first thought.

You see nobody gets energy; in fact by pretending that it’s all straightforward we actually do the students a disservice. Not only are we ignoring the wonder associatied with the idea, we are also denying them the opportunity to engage with the concept at any level beyond the superficial.

Bottom line – nobody gets energy because there’s nothing ‘to get’. Energy is not tangible (alghough it is ‘an indirectly observed quantity’ if you want to sound clever), you can’t hold it in your hand, you can’t weigh it on an electronic balance, you can’t see it, touch it, smell it etc. Yet when the universe was first created there was a certain amount of this put in to the mix (actually now that I think about it the mix itself was energy (with perhaps just a little dash of time)), and it’s all still there today. Its form can change, but the energy itself can’t ever disappear – no sirree bob.

It could be argued that it is in fact merely an accountant’s trick which enables him to ensure that all actions balance.

Consider the following analogy which I like to use.

If a child asks you ‘what is money?’ you could take a few coins out of your pocket and show them to the child and say ‘this in money’. Now fast forward a couple of decades; all transactions are now done electronically/online and all coins and paper money are no longer legal tender. Now how do you explain what money is?

Well it’s a means of payment for goods and services, right? Somebody sells you an orange and you agree to transfer into their account a set amount of this ‘money’. And now that the shopkeeper has this money in his account he can use it to buy something else. So it’s a bit like a transferrable IOU.

Now energy is a bit like this, but there is only a certain amount of IOU’s in the universe and this was set when the universe first came into being (I’m not sure if we know how much energy is in the universe – presumably we do?), although to complicate matters since the early part of the last century (thank you Albert) we now know that all matter (‘stuff’) is basically energy in another form.

Anyone still with me?

Now the point of all of this  is to highlight once again that there is no reference to this concept on either the Junior Cert or Leaving Cert syllabus. It could be argued that this is because it would be too difficult, but the obvious response to this is that nobody understands Energy as it is currently presented anyway. Students merely learn off the definitions and formulae and if they think about it at all will probably just assume that it’s just another example of Physics being ‘too hard’ to understand.

So what’s the actual point in asking students to learn the definition in the first place?

In fact I’d imagine many students who can give the appropriate definition for Energy (“Energy is a form of Work”) couldn’t follow up by explaining what Work is (it’s a mathematical product of force and displacement to give the simplified version).

At Junior Cert level students are expected to be able to show how light and sound are forms of energy – again most students should be able to give the correct demonstration but if you ask them how this demonstration verifies that it is is form of energy few will be able to give a convincing answer. In fact while Energy is the single greatest unifying concept in all of science, even that idea alone is not worthy of mention in the sylllabus; as a consequence Energy is seen as just another chapter to be learned off, with (once again) no emphasis on how it ties together everything else.

Now if teaching Junior Cert Science and coming from a Biology or Chemistry background what are the chances of your students developing an appreciation of this all-encompassing concept? – were you ever told about it?

I thought I’d find something on YouTube to illustrate this, but I couldn’t find anything.

What is it about this idea that we want to avoid?

Below are some quotes from other more prominent commentators on this elusive concept:

When Feynman wrote,

“It is important to realize that in physics today, we have no knowledge of what energy is,” he was recognizing that although we

have expressions for various forms of energy from (kinetic, heat, electrical, light, sound etc) we seem to have no idea of what the all-encompassing notion

of “energy” is.

The various forms of energy (½mv2, mgh, ½kx2, qV,mcT, ½I2, ½CV2, etc.) are abstractions not directly observable.

2007 American Association of Physics Teachers

Feynman’s quote in context:

 There is a fact, or if you wish, a law governing all natural phenomena that are known to date. There is no known exception to this law – it is exact so far as we know. The law is called the conservation of energy. It states that there is a certain quantity, which we call “energy,” that does not change in the manifold changes that nature undergoes. That is a most abstract idea, because it is a mathematical principle; it says there is a numerical quantity which does not change when something happens. It is not a description of a mechanism, or anything concrete; it is a strange fact that when we calculate some number and when we finish watching nature go through her tricks and calculate the number again, it is the same. It is important to realize that

in physics today, we have no knowledge of what energy “is.” We do not have a picture that energy comes in little blobs of a definite amount. It is not that way. It is an abstract thing in that it does not tell us the mechanism or the reason for the various formulas.

The Feynman Lectures on Physics Vol I, p 4-1

Good luck to all exam students

Something to take with you into your Science exam tomorrow – the quotes are from Einstein:

Not everything that can be counted counts, and not everything that counts  can be counted.

Imagination is more important than knowledge.

Do not worry about your difficulties in Mathematics. I can assure you mine are still greater.

These exams are all about how good you are at learning stuff ‘off by heart’. Now no society in this day and age needs students who are good at learning stuff by heart so why do we do it – why don’t we spend time teaching students how to think for themselves?
Because that’s a lot harder to assess. So let’s teach something that we can assess and not worry too much about how useful that actually is. ‘That seem a little silly? Consider the following story:

A cop walking his beat one night finds a drunk on his knees, searching for something on the street.
The cop asks the drunk, “What are you doing?”
“Looking for my car keys,” says the drunk.
The cop asks, “Where did you lose your keys?”
“I don’t know,” the man answers.
The cop, a bit perplexed, asks, “Then, why are you looking here if you don’t know where you lost your keys?”
The drunk replies “Because the light is better here, under the streetlight.”

The following is a question on a physics exam at the University of Copenhagen:

“Describe how to determine the height of a skyscraper with a barometer.”

One student replied: “You tie a long piece of string to the neck of the barometer, then lower the barometer from the roof of the skyscraper to the ground. The length of the string plus the length of the barometer will equal the height of the building.”

This highly original answer so incensed the examiner that he failed the student who immediately appealed on the grounds that his answer was indisputably correct.
The university appointed an independent arbiter to decide the case.

The arbiter ruled that the answer was indeed correct, but did not display any noticeable knowledge of physics. It was decided to call the student in and allow him six minutes in which to provide a verbal answer which showed at least a minimal familiarity with the basic principles of physics.

For five minutes the student sat in silence, forehead creased in thought. The arbiter reminded him that time was running out, to which the student replied that he had several extremely relevant answers, but couldn’t make up his mind which to
use.

On being advised to hurry up the student replied:

“First, you could take the barometer up to the roof of the skyscraper, drop it over the edge, and measure the time it takes to reach the ground. The height of the building can then be worked out from this formula I have worked out for you on my text paper here.”
Then the student added, “But, Sir, I wouldn’t recommend it. Bad luck on the barometer.”

“Another alternative”, offered the student, “is this: If the sun is shining you could measure the height of the barometer,then set it on end and measure the length of its shadow. Then you measure the length of the skyscraper’s shadow, and thereafter it is a simple matter of proportional geometry to work out the height of the skyscraper. On the paper is the formula for that as well.”

“But, Sir, if you wanted to be highly scientific about it, you could tie a short piece of string to the barometer and swing it like a pendulum, first at ground level and then on the roof of the skyscraper. The height is worked out by the difference in a gravitational formula, which I have determined here this time on a long sheet of paper with a very long and complicated calculation.”

“Or, Sir, here’s another way, and not a bad one at all. If the skyscraper has an outside emergency staircase, it would be easier to walk up it and mark off the height of the skyscraper in barometer lengths, then add them up.”

“But if you merely wanted to be very boring and very orthodox about the answer you seem to seek, of course, you could use the barometer to measure the air pressure on the roof, and on the ground, and then convert the difference in millibars into feet to give the height of the building.”

“But since we are constantly being exhorted to exercise independence of mind and apply scientific methods, undoubtedly the best way would be to knock on the janitor’s door and say to him ‘If you would like a nice new barometer, I will give you
this one if you tell me the height of this skyscraper’.”

It’s a wonderful story, and when told is usually attributed to the Danish physicist Neils Bohr, but like all great stories is almost definitely apocryphal.

Good luck in the exam 🙂