I recently had an experience that hit home the concern of new teachers leaving the profession.
I spoke with a new teacher who had only graduated at the end of last year. Let’s call her Lisa. By all accounts she was a capable new teacher, knew her content well, delivered engaging lessons to her students, was willing to learn herself, and important, passionate about wanting to teach and motivate students to science.
And, last year, I was excited to hear that a local well known school with a strong reputation was considering her employment.
When I met her again last week, I discovered she had left the profession. She was burnt out.
The school placement fell through and instead got employment at another school. This school has its challenges especially where it is socio-economically, and I am sure there are dedicated teachers there.
However, Lisa’s experiences were far from supportive. She arrived discovering that each teacher was working on their own unit of work, there was no collaboration in producing programs across each year. More alarmingly, when Lisa asked to see the programs, she was told that there was no sharing, she had to do it all on her own.
When she had classroom management issues (we will all have them) she got no support from her immediate supervisors. She was left to fend for herself.
To me the attitude she was facing was akin to a parent telling a toddler , “get your own food, I’m busy and I font's care”.
Thus it isn't that surprising she started getting panic attacks, and eventually left.
This resonated with me, as I had a very similar experience in my early career.
I don't think this isolated.
Recently , I heard a similar story from a more experienced teacher who was also placed in another school, who got no support from her faculty, especially with dealing with student issues, from the faculty head no less.
Studies seem to suggest the attrition rates for new teachers can be as high as 25% in the first 5 years and a Commonwealth Study from 2014 found 5.7% teachers leave in any given year - see the link below for further details.
I appreciate the fact that teachers leave for a variety of reasons, misplaced expectations, changes in circumstances, other professional opportunities, but high on the reasons provided in studies is a lack of support.
Being based in NSW, Australia, I refer to the the Department of Education and Training (DET) and DET do have policies in place to support new teachers. But I am concerned that possibly these polices aren't always enacted on.
Add to the fact that many new teachers, especially in government schools, are placed in schools that have a high turnover rate - schools in disadvantaged areas, schools that are remote, or both. Yet, these are the places that need experienced teachers to effective teach in challenging circumstances.
I acknowledge I am no expert in understanding the complexities of the reasons behind the teacher attrition, but as a science educator I am especially cognisant of the need of effective science communicators to advance a passion for science and grow a scientific literacy in our community. And when we see good science educators leave because they get no support, we all lose.
Please add to the conversation - experiences, thoughts, ideas
I just finished watch the film, “The Current War” starting Benedict Cumberbatch and Micahel Shannon
The film was made in 2017, and then received a director’s cut and re-released in 2019.
It was slated for cinema release here in Australia in March 2020, but the COVID pandemic stopped that. The movie being released on Apple and Google for purchase or rental.
For those that don’t know the meaning behind the title, it refers to a competition between two standards of electrical distribution: direct current, or DC, championed by Thomas Edison, and alternating current or AC, championed by George Westinghouse.
By the late 1870s, both men were already well known. Edison, played by Benedict Cumberbatch, had invented the lightbulb, phonograph and started developing a system to distribute electricity to power the light bulbs. He was by then a very famous individual.
Westinghouse, played by Michael Shannon, the great rail engineer and industrialist, had built his fame and fortune by inventing the train air brake which made a significant impact on the development of the rail industry. By the late 1870’s and into the ‘80s, Westinghouse sought to distribute electricity by a much better system, AC. Its chief advantage: it could be transformed, thus increasing its voltage, and then transport it long distances without significant power loss. DC distribution was only effective I sort distance and thus would require power stations every few km or so, and this could only be practical in large cities.
The movie carries the story as to how these two men responded to the competition between the two systems, culminating in the tender to light the 1893 Chicago World Fair.
It shows the unscrupulous tactics employed by one of them to discredit the other.
I resist giving too much away, since you may not be fully familiar to the story and would like to see the movie for yourself with fresh eyes.
Knowing the story pretty well, I was impressed by the movie to present the story with some balance. Yes, there is a bit of a ‘villain’ element, but the character portrayal isn’t too one dimensional, and you get a sense of the humanity of all the main characters represented.
Edison and Westinghouse are usually the two figures that come to mind in the “Battle of the Currents” how it is also referred, but often Nikola Tesla is left out.
I am glad the movie chooses to include Tesla’s in the story, played by Nicholas Hoult, as he makes a significant contribution to the story.
Having read a few other reviews, there was some criticism that Tesla wasn’t explored further. He did develop the AC induction motor that contributed to the eventual success of the AC distribution. But this movie is really about the vying for the better system for electrical distribution, which was predominantly a battle between Edison and Westinghouse.
Like all movies that start of with “Inspired by true events” there are some inaccuracies. Two events are juxtaposed towards the end that did not occur at the same time. In fact one occurred three years before the other. The death of a character occurred 5 years after the time portrayed. In both cases the director clearly made some changes to the story to better fit in with the narrative of the story.
I don’t think this seriously detracts from the story as a whole.
And there are parts that are stylistic and probably didn't happen. Did investor arrive on a Westinghouse train to be greatly by Edison in the snow with a circle of lights?
Apart from the excellent Cumberbatch, Shannon, and Hoult, the supporting cast also do a great job, with Tom Holland playing Edison’s secretary Samual Insull, Matthew Macfadyen playing JP Morgan and Katherine Waterston, playing Westnhouse’s wife, Marguerite.
Cinematography is excellent as is the soundtrack and the director, Alfonso Gomez-Rejon, uses both well to advance the story as well as connect the two main protagonists
The movie is light on physics, it is a hollywood movie after all, but I think serves Physics well as it gives a context to why AC distribution won out in the day.
So overall I enjoyed the movie and recommend it. I would especially encourage students of physics watch it, to give a bit of historical context to electricity and its supply.
or A LESSON UNITS, UNCERTAINTY AND SIGNIFICANT FIGURES
I find students when they start a physics course, have a weak understanding of how measurement works and how values are discussed, and so I cover key concepts of units, uncertainty and quoting of significant figures, before I start the physics course proper.
What follows is a an activity I do with the students over the course of 1-2 hours.
(I include some thoughts in red)
Determining the Density of a pice of paper
Divide your class into groups of 3
Give each group a single sheet of A4 (or 'letter') sheet of paper and ask the to determine its density as accurately as possible.
Give as little instructions possible but provide them only a meter ruler and access to a set of digital scales.
Finding the length and width is relatively straight forward, but the thickness is another matter.
I find the students generally fall into two camps, they either fold the paper multiple times to ge a thicker section (which has its limitations) or they ask for a stack of paper and measure that (again, the size of the stack contributes to uncertainty)
Once they determine the dimensions and the mass, and thus calculate density, get them to write their answer on the board.
When I survey their responses, most get similar 'numbers', however, there will be some with different units (I insist on them quoting units) and many over quote significant figures.
So as I discuss the results in the class I ask
"Are these results the same?"
To the ones who over quote numbers, I ask "how confident are you of those number?"
I then ask about the thickness measurements, "How certain are you about the number being that precise value?"
This then all leads to a discussion on
- talking the same 'language' - SI units
- how we express our uncertainties
- the role of significant figures (check out my video here)
At this point , teach the points measured above, including how to express uncertainties
Once you have covered the concepts , get students to repeat the task, but prior, teach them how to use a micrometer.
Students now need to determine the density, using same units, and quoting with % error and in correct significant figures.
When results are compared on the board, all their results should fall within the uncertainty of the over the results (hopefully :) ). This could be graphed to make it more clear.
Feel free to provide feedback below and any modifications you tried
I was asked in one of my comments on YouTube why 'g' was designated as -9.8 m/s2.
In their words "if gravity goes down , why isn't it positive."
So I thought I would respond as I am sure there are many students who ask the same question when they start a course in physics.
When we determine 'g' as an acceleration we commonly use the Newtonian view of gravity as a force, and thus when we divide the force by the mass we get acceleration.
But it is better to think of 'g' as the gravitational field strength, or in another way, the value of the energy by way of its position in gravitational field per unit mass. (we can also call this conventionally, the amount of potential energy per unit mass) the symbol for potential energy is U
So g = U/m.
But U, the potential energy is deemed to be negative*, because
a. moving away from the mass generating the field always increases U and
b. U is set as 0 at ∞
So how can you always increase U by going up to 0?
that is why in texts U = -GMm/r
(I encourage you to look at my video on GPE Explained for more detail)
So if U is always negative, the so is U/m, which is g
So that is why books use -9.8m/s/s for gravitational acceleration, and therefore any vector going down, such as velocity or displacement will also need to be negative.
* the choice to have U = 0 at ∞ is arbitrary and is set by convention. There is no physical reason why it should be negative. To to ensure consistency, it is agreed that U = 0 at ∞