Diagnostic Questions

Jul 11, 2017

Somehow I stumbled across or was led to:


I probably found the site via a link on the “Mr. Barton” maths website. Craig Barton appears to be the originator of or a significant contributor to this site. Following an entertaining talk by Miles Berry at the CAS Birmingham conference about Project Quantum I decided to try out some of the DQ Computing questions. I particularly like the opportunity the platform gives to students to explain why they chose a particular option as this gives more info on the misunderstanding behind a “wrong answer”.  The Computing A-Level material on the DQ sitelooks good but the number of questions is a bit “thin” in some areas. So I am going to add some questions on the “patchy” topics and see how they are received.


Times change I guess

Jul 2, 2016

Was this the style of academic writing a few decades ago?

... partly from a long-term standing avocational interest in the philosophy of science. Somehow, whatever their pedagogic utility and their abstract plausibility, those notions did not at all fit the enterprise that historical study displayed. Yet they were and are fundamental to many discussions of science, and their failures of verisimilitude therefore seemed thoroughly worth pursuing.

Kuhn, Structure of Scientific Revolutions 

It took me three goes at reading that to understand it.

When attempting to solve suvat equations be clear as from where measurements are taken. The place where initial velocity, u, is defined is s=0 & the time is t=0.

It is unusual for a suvat question to involve two particles that start from different points or times but collide at some later time.
The solution approach is to define the suvat equations separately for each particles with their own time reference. The next key step is to make the two time references the same, example would be good here.

I believe that solving questions about two objects colliding can be fairly easily solved using v_t graphs.

Khan Academy

Aug 27, 2011

15 minute, “bite-sized” lectures on a wide range of mathematical (and other) topics. Level is (mainly) american high-school and college/undergraduate – equivalent to UK A-Level and first year undergraduate.

Accessible via You Tube or dedicated web site


My first reaction was “a bit naff”. The “graphics” are very limited.

Then I realised, the simplicity and limits of the delivery of the content is its virtue. Being You tube published and delivered the content is limited in length to around 10 minutes. Compared to the one hour lesson or lecture little material can be covered but this is ideal since the student’s attention doesn’t wander. Of course as the content is online and without charge (*), the material can be accessed anywhere there is a browsing device (I almost wrote computer) and an internet connection. Online material can of course be paused and replayed as many times the student requires or has interest to do so. The material is still delivered in a linear fashion and is teacher-led but I think there is virtue in this delivery building from the simple to complex. (**) Khan is extending the idea of academy so that real students can enroll on courses and receive feedback. It will be interesting to see if this will be run on an not-for-profit basis. Personally, I wouldn’t begrudge Salman Khan making some money from this if you look at the vast amount of material that has been already created and made available.

Another positive is the technology to create the content is widely available (at a price) and the skills to use the technology are essentially the same as delivering a seminar/lecture. The lecturer (it appears) write on a tablet which displays on a computer screen, analogous to writing on (black) paper with coloured pens and records an audio commentary simultaneously. The content is recorded “real time” as a digital file which is uploaded to You Tube and “voila” the world has access to a lesson on aldol reactions or limits or photosynthesis or .. or ..

The lecturer/ owner/ faculty member is Sal(man) Khan and ex-Hedge Fund analyst turned social-entrepreneur. I was originally suspicious and cynical about his motives but I have been won over by his engaging, self-deprecating personality


Salman Khan talk at TED 2011 (from ted.com)

I like his joke that his cousins preferred him on You Tube than in person.

Of course, the real acid test is whether students who are approaching the content for the first or second time can follow and understand the content.

(*) Of course there are cost for the device and network access charges

(**) The value in “network” delivery rather than hierarchical is a discussion for a another time.