Triple A Learning IB Blogs

Single slit diffraction

Andy Cockburn — Sun, 05 Feb 2012 11:32:57 +0000

I was introducing single slit diffraction the other day. I shone a laser through a variable width slit and showed that when I narrowed the slit the light spread more. I wanted students to take some measurements but it would not be easy for them to measure slit width so I directed them towards Walter Fendt’s single slit diffraction applet. They were able to quickly plot a graph of wavelength against angle of first minimum and also slit width against angle of first minimum. I thought it was a really good introduction to the topic because students asked lots of questions about the shape of the diffraction pattern, where to measure to etc. I found myself saying good question, we are going to explain that in the next lesson on quite a few occasions.

limits on knowing

Eileen Dombrowski — Sun, 05 Feb 2012 00:15:27 +0000

http://www.youtube.com/watch?v=LYwTIdagGSo

What ethical restraints do we recognize as we seek knowledge? This question, which runs through areas of knowledge in TOK, finds a particular focus this week in photographs just released of the Mashco-Piro tribe in southeastern Peru. The photographs, taken from a distance, renew the place of this group as an example of an “uncontacted” tribe in continuing issues of cultural and environmental conservation.

Paradoxically, it is only through knowing that the uncontacted tribes exist and knowing about the forces that threaten them that we can even consider responsibilities to these people and their environment. Yet that essential knowledge might point to a conclusion that there are limits: do not seek to contact and learn more, because we damage in the process the very human beings we want to know more about.

Clearly, though, much contact with the tribes of Peru is not motivated primarily by the desire to gain knowledge but the desire to gain land and resources. The organization Survival gives reasons on its website for leaving groups uncontacted, noting threats from disease and violence, and asks for signatures on a petition: “Oil workers and illegal loggers are invading the lands of uncontacted tribes in Peru. Please sign the petition, and we’ll deliver it to Peru’s President Humala.”

Anthropologist Glen H Shepard Jr (“Close Encounters of the Mashco Kind”) points out the problematic language used to describe this tribe: “It is an extraordinary thing to consider, this encounter with nomadic hunter-gatherers at the turn of a century that had seen the miracle of space travel and the specter of nuclear holocaust. And yet to call such people “primitive” or “uncontacted” is something of a misnomer, since the Mashco-Piro and other isolated groups have not remained stuck in the Stone Age since time immemorial. Rather, they have resorted to “voluntary isolation” (Shepard’s 1996 report “Los grupos indígenas aislados del Río Piedras”) in modern times in order to survive.”

If you prefer to avoid disturbing news accounts of atrocity, please do not read this account: “Why do they hide?”

The news reports and pictures of the Mashco-Piro could well spark a good discussion in a TOK class not just on ethical responsibility but the importance of knowledge – anthropological in this case — in being able to discuss such responsibility intelligibly. It could also place discussion of knowledge and ethics in political and economic context, with real implications for the survival of human groups.

Eileen Dombrowski

INDEX to TOK meets global citizenship

References

Glenn H Shepard Jr, “Close Encounters of the Mashco Kind”, Anthropology News, http://www.anthropology-news.org/index.php/2012/01/26/close-encounters-of-the-mashco-kind/

“Up close one year later: startling new photos of uncontacted Indians released”, Survival http://www.uncontactedtribes.org/news/8055

“The Uncontacted Indians of Peru”, Survival. http://www.survivalinternational.org/tribes/isolatedperu

“Why do they hide?” Survival. http://www.survivalinternational.org/articles/3104-why-do-they-hide

cat-free images of galaxies

Eileen Dombrowski — Fri, 03 Feb 2012 22:47:21 +0000

Space cats? After yesterday’s posting, you might find it as interesting as I do to see how images of galaxies from the Hubble space telescope are actually made. The images are indeed “made” rather than simply “taken”. When we talk about manipulating images in class, we are generally dealing with selected views or gradations of deception. The Hubble images are something different — a combination of “takes” not for a representation of a “better reality” but for a “better representation” of reality.

It’s a 2 and a half minute video, perhaps worth playing shortly after Space Cats

Eileen Dombrowski

INDEX to TOK meets global citizenship

Is it real?

David — Fri, 03 Feb 2012 12:00:20 +0000

My children love the Julia Donaldson story, ‘The Stick Man’ but did you know that we had our own chemical stick man.

Apparently it exists…..

…… but I am yet to be convinced.

Does anybody have a name for this molecule?

TOK and Curriculum Design

triplea_cw — Fri, 03 Feb 2012 08:42:39 +0000

Planning Ahead

As the new year starts (for us at least) the annual revision of the TOK scheme of work occurs. The reflection on the results and the marking always leads to some insight or another. Requesting the essay back now is both painless and efficient (if you have a good printer!). The examiner’s comments can contain some insights, although the new e-marking system is still having some teething problems.

I think the big challenge for any TOK teacher is to shifting away from the classic Introduction to Knowledge, Ways of Knowing, Areas of Acknowledge structure to teaching the course. This structure is a good safety net for both teachers and students, and in workshops I have always supported it as the first step. But most experienced teachers would acknowledge the limitations of this structure. However, there is a balance between getting the students to understand the way of thinking required in TOK and understanding its particular conceptual framework. All courses should spend time introducing the subject’s concepts and its conceptual framework as well as the skills required. But when this is completed, teachers have an excellent opportunity to provide depth to their student’s understanding and hopefully their assessments. Breaking down the assessment requirements is an ideal way of starting and ensure these are integrated into any teaching structure.

Nick Alchin outlined a good structure many years ago – from certainty to uncertainty (assumed to be Maths to Arts). There is another approach. This can be to identify a number of key concepts that appear regularly in the Titles and design a course around them. My choices under the title, ‘Introduction to the Principles of Knowledge – discipline-based thinking’, are:

Certainty in Knowledge: The Myth of Objectivity and Subjectivity
Does Everything need an Explanation?
Looking for Patterns: Chaos, Order, and Security
Time and Knowledge: Between Past and Future
CAS and TOK

Book/Cover/Race/Sense Perception

triplea_cw — Fri, 03 Feb 2012 04:07:21 +0000

With my wife recently called for jury duty and the subsequent discussions about the role of the citizen in the justice system, I decided to do some research. A recent controversy in the UK caught my eye. In this article, “Twitter fury over ‘surprise rape’ article gets UniLad suspended“ it was claimed that “head of the CPS in London has said that jurors’ preconceptions about women has a negative impact on rape conviction rates.”

It reminded me of a story I used to use in class discussions. A researcher in the late 1970s became concerned about racial stereotypes after an instance with his son. He was driving through a city in America when a black man ran across the road. He son apparently turned and said some along the lines of ‘I wonder who he has just robbed’. The strong association of a black man running and a crime having been committed shocked the father. A former student emailed me a number of years ago with a follow-up story to this discussion. In response to a heated debate, a group of British students has run a very informal experiment. They chose 4 London underground stations from 4 different socio-demographic backgrounds and staged an event in each of them. Casual observations where made, and they used these to draw a conclusion. The event was a young man running down the platform. How would London travellers react to this event at each station?

In the course of 20 minutes and a turnover of passengers, they watched and gauged the reactions of the passengers to a ‘white man’, an ‘Indian man’, a ‘black man’ and a ‘Muslim man’ running down the platform. My former student was intrigued by the methodology of this experiment and sent me some reflections, partly to see if his TOK skills were still up to scratch and partly to give me fodder for the classroom. They certainly were, but he could not find fault with the conclusions they drew.

Well, in response to the first part, I tried to find the reference to the head of the CPS (in London). I came up with a report from Professor Cheryl Thomas, titled, ‘Are juries fair?’. Fascinatingly, she is a member of the Centre for Empirical Legal Studies in the Faculty of Laws at University College London. The descriptor ‘empirical’ in this title caught my eye.

The report Professor Thomas wrote was from ‘Analytical Services’ which claims to support ‘effective policy development and delivery within the Ministry of Justice by providing high-quality social research, statistics and economic analysis to influence decision-making and encourage informed debate’. Again, the claim ‘high-quality social research, statistics and economic analysis’ caught my eye.

The topic heavily engages with the issue of reason, language, emotion and perception and leads to the issue of methodology in the human sciences.

The Summary (p. i) provides a good insight into its worth as a stimulus for discussion:

“Summary

This research asks: How fair is the jury decision-making process? It explores a number of aspects of jury fairness for the first time in this country, and asks specifically:

Do all-White juries discriminate against BME defendants?
Do jurors racially stereotype defendants?
Do juries at certain courts rarely convict?
Do juries rarely convict on certain offences?
Do jurors understand legal directions?
Do jurors know what to do about improper conduct in the jury room?
Are jurors aware of media coverage of their cases?
How is the internet affecting jury trials?

The research used a multi-method approach to examine these issues:

case simulation with real juries at Crown Courts (involving 797 jurors on 68 juries);
large-scale analysis of all actual jury verdicts in 2006–08 (over 68,000 verdicts);
post-verdict survey of jurors (668 jurors in 62 cases).

The study found little evidence that juries are not fair. However, it identifies several areas where the criminal justice system should better assist jurors in performing this vital role. The study also demonstrates that section 8 of the Contempt of Court Act 1981 does not prevent comprehensive research about how juries reach their verdicts and that research from other jurisdictions should not be relied upon to understand juries in this country.”

CCD Video

stefan_merchant — Fri, 03 Feb 2012 01:32:52 +0000

How a CCD works is a difficult concept for me. I struggle in teaching this part of the syllabus effectively. The invention of the CCD was a tremendous step forward for technology and was recognized by the awarding of the Nobel Prize in 2009. Wired magazine has a nice article about the CCD and Nobel Prize and there are several videos on YouTube. My favourite is

It uses a Prezi to explain how a CCD works. If you don’t know about Prezi it is worth taking a look. I suspect that some of your students are using Prezi in their other classes if not Physics.

space cats

Eileen Dombrowski — Thu, 02 Feb 2012 16:42:46 +0000

Take 3 minutes out of your day to watch this splendid spoof. You might even want to use it in class if you’ve been talking about either the human tendency to see faces in random shapes (pareidolia, relevant to sense perception) or manipulation of photographs. After some serious treatment, you may want to lighten the class with a laugh.

Eileen Dombrowski

INDEX to TOK meets global citizenship

Space Cats http://www.youtube.com/watch?v=_P-yAkBbIV0

Bonding – Topic 4 & 14 – Ionic, Covalent and Metallic bonding

David — Thu, 02 Feb 2012 12:00:58 +0000

Here is a pretty cool youtube video that your students will probably love -it is quite simplistic though, but not bad for students to view in their own time. You could ask your students to use this as a starting point for explaining (in more depth) about the different types of bonding (maybe for a homework exercise?)

digital learning day

Steve Money — Thu, 02 Feb 2012 07:53:29 +0000

Several events are taking place today in the USA as schools recognize the first national Digital Learning Day, planned by the Alliance for Excellent Education.

To commemorate the occasion, Education Secretary Arne Duncan and other education leaders are fielding questions on digital learning and policy at a national town hall event that also is profiling educators who were filmed using technology in their classrooms.

So what?

The writer of this blog post offers suggestions and resources for teachers celebrating Digital Learning Day. The post includes archives of reports on education technology dating back the 70′s. And she challenges educators to observe the occasion by starting a conversation, trying one new thing, and showcasing a success.