A stupidly simple mnemonic for acceleration graphs

When working with position/time graphs of accelerated motion, it is easy to confuse the dire
ction of velocity with the direction of acceleration. for example, look at the two graphs below:

parabola right       parabola left

Many students will instinctively say that the first graph is positive acceleration, while the second graph is negative. In fact, these are the same graph, as you can see here:

parabola fullIt is a single parabola, representing positive acceleration.

So how do I get kids to recognize positive and negative acceleration? Using the following, stupidly simple trick:

parabola 2

Positive face

parabola 3

Negative face

It’s really that simple. Any part part of the smile, be it a corner of the mouth smirk or a full on grin, still looks positive. Any part of the frown still looks negative. And that’s it.






Flippity flash cards

I like tools that are flexible and easy to use. So while I was recently looking for a flash card tool to use with my students (there are many!) I found that lots of them required registering, or were pretty but limited in what they did, or wouldn’t allow images or text formatting. Formatting is important – I teach science, so I use a lot of subscripts and superscripts.

I was pleased to find (somewhere on page three or four of my search) flippity.net. This simple tool uses a google sheet to generate flashcards. You grab a template, enter your information in two columns (the two sides of the flash card), along with colour formatting if so desired. Publish your spreadsheet, grab the link, and paste the link into the second page of the sheet, and voila, instant flash card set. No sign in required.

flashcard image

There are ads displayed prominently on the site, which may make it unsuitable for some. But as a simple, non-login flashcard game/study aid, that allows html formatting and embedding urls for images and video, I think it has a lot of potential. I could see having students easily generate flashcards for themselves and each other as well.

The site also has templates for generating quizzes, a Jeopardy style game, name picker and  progress indicator, so there’s a lot of potential there.


A slightly different take on Ahmed Mohamed

As you have probably heard, 14 year old Ahmed Mohamed was taken away from school on Monday, in handcuffs, for bringing a homemade clock to school.

In the bright distant hindsight of a social media shitstorm, the teachers, the principal, the police, and everyone were to blame for misunderstanding (at best) or racial profiling and racism (at worst), and the claims of officials, as reported by the Washington Post, are seen as lame:

School officials, however, insist that their staff and police acted appropriately in investigating the device as a potential threat.

“The information that has been made public to this point has been very unbalanced,” Lesley Weaver, a spokeswoman for Irving Independent School District, said at a Wednesday news conference. “We always ask our students and staff to immediately report if they observe any suspicious items or if they observe any suspicious behavior.

Reviewing the sequence of events, roughly

  1. Ahmed builds a clock to show his teachers and friends the hobby he is proud of.
  2. He brings the clock to school, and shows his first teacher, in engineering class (wait, they have engineering class in ninth grade? Wish I had that!)
  3. the teacher reportedly said something like “That’s really nice, I would advise you not to show any other teachers.”
  4. Ahmed carries it around, and an alarm goes off in English class. The English teacher thinks the clock looks suspicious.
  5. Ahmed gets questioned by the school authorities, then the police, and gets taken away.

So what went wrong, and how did this young man’s awesome hobby turn out so badly for him that day?

As much as I would like to chastise the English teacher and principal, I think they probably had little choice. It would not surprise me if it were in fact law that anything suspicious must be reported, the same way we are required to report suspected abuse to children’s aid immediately. So while they may have been ignorant and fearful, it may have made no difference – if someone thought the device looked suspicious, they may have had an obligation to call the police.

Here’s the clock, by the way. Innocuous enough to anyone who has the slightest understanding of electronics. Scary as hell to anyone who doesn’t but has watched too many spy movies.

So that really leaves Ahmed himself, the Engineering teacher, and the police.

Ahmed is a 14 year old with complete first hand knowledge of the workings of his clock (and no first hand knowledge of what a bomb looks like), a project he was proud of. So while some might say he should have known it looked like a bomb, I think that in itself ascribes lost innocence to the boy. I think he can safely be exonerated, though the harsh reality has made itself known to him, and I suspect he will be overly cautious in the future. Sadly.

The Engineering teacher apparently recognized it for what it was, and also recognized that other teachers may not. Since that teacher did not report the clock as suspicious, he clearly knew it was safe, but did warn Ahmed that others might find it suspicious. But this is where, as a teacher, I find there was a missed opportunity. If he knew it might be considered suspicious, and knew that suspicious objects could get Ahmed in trouble, he could have done something about it. Something such as “Hey, you know what? this case makes it look sinister to people who don’t know about this stuff. Why don’t you let me look after it for now so it doesn’t cause any trouble, and you can pick it up after school.” Or even better: “”Hey, you know what? this case makes it look sinister to people who don’t know about this stuff. Why don’t you let me look after it for now and later we can make a cooler case for it later on.”

That leaves the police. Were any of the police members of the bomb squad? Did any of them know what a bomb actually looks like, or have any training in electronics? Probably not. So they arrive to find a device that someone was suspicious of, and they did what they do (when you’re a hammer, everything looks like a nail), which is apply pressure to “suspects” to try to elicit a confession. They overstepped their authority when they failed to let him call his father, unless they too are under very specific guidelines to treat any “perceived terrorist threat” with patriot act -like authority.

So it is really hard to lay heavy blame in any one place. The first teacher could have been more helpful, and the police could have been less heavy handed (much, much less). The principal could have called the father, and could have been more supportive. Racism, whether overt or subconscious, most likely played a role, and that is in part (or largely) due to the relentless news coverage of “The War on Terror” and the resulting heightened fear.

The whole sequence was a tragedy of errors, and could (should) have been mitigated or stopped at many points by someone doing more than “just following orders”, but sadly was not.

I just hope that Ahmed continues to follow his dreams, and make fabulous things. I hope more people become aware that kids can make fabulous things that aren’t scary, and that this brings a little more awareness of issues of racial profiling and police behaviour, particularly towards children in our schools.

You go Ahmed! Keep making cool stuff!




There is an entrenched, legislated fear response, fueled by constant reminders of “War on Terror” and “See something, say something”. At every level the guidelines are essentially, “if you see something suspicious, report it to your superior”. So the slightest little suspicion automatically gets passed up the line, up the line up the line again until the police are called, and since it is a “suspicion of terrorism” the police are already on a heightened alertness, and operating under an assumption that they are being called because of a legitimate threat.

Checks and balances people, we need checks and balances.



More on my trip down the SBG road

I wrote earlier about my decision to go SBG, and my early observations of implementation. Well, at about the half-way mark through the year I compiled my thoughts about it, and put them into a video. So if you have a few minutes, let me walk you through my experience so far:

Is Physics a language class?

When I teach Physics, I like to focus heavily on the conceptual side, as well as the process of problem solving and how to think about problems in general, rather than just the mechanics of the math. After all, the math we do in Physics is typically a year or more behind what they are actually studying in Math class, so they should be pretty good at it. In other words, I like to get metacognitive about the subject.

Physics is not exactly about the real world. Physics is about studying mathematical representations (models) of reality, in hopes that those representations can be predictive. For the cognoscenti, real science hides in the places where the math does not predict what we see in the real world, but we rarely delve into those places in school. Instead, we focus on how the models do match and predict reality. In any event, we need to translate what we see around us into math in order to manipulate the model, and then translate it back from math to real world.

It is that translation piece that got me thinking about the title of this post. When we do physics, we are really “translating” from the language of the real world top the language of mathematics – a bit like translating a question from German to English, answering the question in English, and then translating it back – the grammar doesn’t always match, so we have to be judicious in how we translate. And when we study languages we learn to recognize the nuances of each, and the differences in how they work to express things. Likewise in Physics, we need to recognize how a mathematical representation is similar to, and how it differs from the real world.  There are of course other ways to represent reality – artistic, linguistic, and so on, as well as other analogies for translation (thinking gene expression here…), but I’m not sure they convey the same sense of how Physics operates.

Here’s the thing – though I have learned other languages, I have never taught other languages, so I don’t really have a sense of the metacognition of that process. I think it’s about time I explored that in order to develop a full toolkit to help my students understand more about the process of doing Physics.


We need more invisible refrigerators

This year I am taking part in an EdTech/21st century year-long PD program called Cohort21. We had our first face to face session last Saturday, and the morning discussion centred around the use of technology in the classroom. The following are some thoughts arising from that session:

During the morning discussion of technology in education at the first face to face session of Cohort 21 we discussed the idea that technology should be transparent, invisible, in the background supporting learning, rather than being the focus. Like a refrigerator – it does an important job, but we don’t focus on refrigerators when preparing dinner, we focus on the food. Since we don’t focus on the refrigerator, it is effectively invisible when cooking.

Digital technology, however, is not. While we really want it to be, we have to spend a fair bit of and energy getting the applications to do what we want, making sure the students know how to use them properly (and actually use them…), and adjusting our methods to fit the paradigm of the software. All of this prevents the software (educational and otherwise) from becoming invisible.

I spend a good deal of time checking out educational apps and software, hoping for new tools that can support my classroom without getting in the way. Most often I find parts of of each of them to be quite desirable, and then other parts that make it almost useless (think smartphone apps for marking MC quizzes, but don’t give any feedback to the students).

Evernote is one application that does an awful lot, and is very flexible for recording observations, note-taking, tracking progress, and really anything else you want to make note of. And it’s shareable. Google Apps is on it’s way, but not there yet (but if Evernote could save to Google Drive, now that would be something!). But I’m having trouble thinking of other software that might fit into this category.

Most Educational software requires us to deliver in a certain way, or assess in a certain way. What we really need in EdTech is more invisible refrigerators.

A little organizational idea

So, I had this idea. And here’s the funny part – it came to me in a dream. No. Seriously. But it’s not the sort of thing I would ever think up, so I must have heard it from someone and it’s been fermenting in my brain for lord knows how long. But anyway…

In this dream I was volunteering somewhere (because it was a dream the “somewhere” was kind of vague, but maybe a museum?), and there was a box full of little slips of paper. On each slip was a job that needed doing. We volunteers would take a slip, do the job, initial it, and drop it in the “done” box.

See? beautifully simple. Totally unlike me.

This little idea, id seems to me, would be perfect in the classroom (and is probably being used in classrooms all over the place – like I said, this is not likely an original idea). Not only can you get jobs done – sorting craft supplies, organizing resources, returning materials to the library, etc – you have a record of who did what, and you can do a quick check to see how well each job was done.

While this would likely be very useful in an elementary class, an art room, music class, etc, I am not entirely sure how to implement it in a grade 11 Physics class, nor what motivation I could use even if I did have jobs.

But if I was organizing volunteers…

Desmos is another great math tool

Yesterday I wrote about g(Math), a tool for adding formulas and graphs into Google docs, like an equation editor on steroids. Today I’m going to talk about Desmos, a full-featured, web-based standalone graphing calculator.

Desmos can be run from the website, or installed as an app in Chrome. You don’t need an account to use it, but if you create an account you can save your work – even saving a copy to Google Drive, which is nice. The interface is clean, with the list of functions down the left side, and a large central grid (which can be switched between Cartesian and polar) to display functions. It responds well to double touch, so using it on an interactive whiteboard is easy.

There are many, many saved examples on the Desmos site which highlight it’s capabilities – including animation and drawing pictures with multiple equations.

I’ve started using it to illustrate the parabolic functions of acceleration, finding the roots, intersection of functions (solving two equations and two unknowns), and illustrating standing waves and beat frequency. I’ve just scratched the surface – there is a lot more that can be done with it, I just need to find the time to figure out what all else it can do. But for teaching transformations of functions? Just throw in a function with sliders and watch what happens. It is a very user-friendly interactive tool.

It’s teacher friendly, student friendly, works beautifully on the interactive white board, it runs animations, and it’s fun. What’s not to like?


g(Math) is a great addition to Docs and Sheets

Many schools use Google Drive with Docs, Sheets, Presentations, and any number of other plugins. But in Math and Science, there are a number of shortcomings. Hand drawn diagrams and equations are not easy to insert, and up until recently, the equation editor was quite limited.

But with g(Math), you have the full power of LaTex equation formatting at your disposal, and can generate complex formulas including vector arrows, matrices, and pretty much anything you might want. There is a bit of a learning curve for anyone not familiar with LaTeX syntax, but there is a large set of tools that can be used to generate a template which can be modified as necessary. With practice, anyone who is at all familiar with markup languages (such as html) will figure it out pretty quickly.


In addition to equations, you can also use g(Math) to generate graphs of functions that can be inserted into a document, which is very handy when generating Physics notes for class. gmath1

In Sheets, g(Math) lets you insert equations and graphs into cells, but also gives you some options for stats, and a nifty feature that will generate a form using the equation and graph images inserted into cells – a nifty feature for creating quizzes.


This is a great addition to GAFE, particularly for math and science. It would be nice to see it included with Presentation too, but until then one can always cut and paste.

Now we just need to work on getting digital ink into Google docs…


The straw that fixed the camel’s back – Moving to SBG

I am always on the lookout for ways to improve my courses. Recent(ish) innovations include flipped learning, layered curriculum, modelling, SBG, and on and on. I like them all – or rather, I like most of most of them, and parts of all of them. But inevitably there is something about them that either doesn’t fit, whether it’s with my subject, my teaching style, or the requirements of our Ontario curriculum, there always seems to be something.

But recently, while perusing again through resources on SBG (Standards Based Grading), I re-read this post by Kelly O’Shea. But this time, something clicked, and I realized how I could mesh SBG with the Ontario ministry requirements of assessment and evaluation, layer the content in a meaningful way, and have it all make sense. And It all works with how I like to do things, which is probably the most important thing.

So here’s what I’m doing:

I started by going through the list of ministry expectations for the course, and then through all of my tests and assignments, and figured out exactly what it is I want my students to know. The list came out at 82 things, which were further subdivided into categories of Knowledge, Inquiry, Communication and Application (it’s an Ontario thing…). I also identified which standards involved core knowledge and skills, and which were more advanced.

Every standard is graded on a 0-3 proficiency scale, and all standards are effectively weighted equally. The core skills, such as  I can draw and interpret d/t and v/t graphs in uniform motion, and I can identify/determine whether forces are balanced, will earn students a score up to B+ (we don’t officially have letter grades here, we have number levels, but they correlate: 1 is a D, 2 a C, 3 a B, 4 an A. You get the idea). Advanced skills add on top, bringing the mark up into A territory. Which means, technically, a student could get a B+ in the course without ever even attempting an advanced skill (but hey, if they are ninjas with the core skills, why not?). I have a few additional rules – mostly to force conversations of a student earns a 0 or 1 on a core standard, but you probably get the gist.

On any given assessment, I will typically have three or so questions for each standard (sometimes multiple standards per question), and will generate an aggregate grade of 0-3 (whole numbers only)  for each standard based on the results. The only way to get a 3 is to get 3’s on all questions addressing that standard. Two 3’s and a 2 is a 2 (since they have not fully mastered that standard). Errors on things that are not addressed by a standard in a question are given feedback, but not penalized. There are no overall grades for tests and assignments, only on standards.

Students will have regular opportunities to be re-assessed on standards.

I have only been using this method of assessment for a month now, and I have already noticed many  advantages. Because all standards are weighted equally, it forces me to create assessments that cover a balance of topics, as well as a balance of core and advanced level questions. Students and I know exactly where their strengths and weaknesses lie, and ask for specific assistance in order to achieve proficiency. And, frankly, as I start working on my first set of reports, It is ridiculously easy, as at a glance I can see a student’s progress through each standard.

I have to say, so far so good!