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Tuesday, June 9, 2009

Target Practice

Ever see a student "graph" something by obviously just sort of copying the general shape he sees on his graphing calculator window? Come on, you know you have. Making a nice graph is a tedious procedure for an adolescent. Invariably someone is just going to wing it.

Exasperated with saying "plot points and draw a smooth curve" over and over, I hit on an analogy that sticks. I've never seen such pretty hand-drawn graphs as this year.

This is pretty famous on the Internet, and maybe you have seen it:

It is supposedly located in the men's bathroom in Amsterdam's Schiphol Airport. See the irregular black spot? That's a housefly painted on the porcelain.

Why on Earth would they do that? Because your aim improves when you have a target. The flies keep the bathroom cleaner for longer. In my search for images, I even found that a company is marketing a sticker called "the urinal fly."

What this has to do with graphing, of course, is in my exhortation for students to plot points before sketching a curve. After telling the story, now I can say, "Remember the urinal flies in Amsterdam? Give yourself a target." From my notes:

Now that is some explicit direct instruction! I'm a fan of the book Made to Stick, but aside from the six key principles simplicity, unexpectedness, concreteness, credibility, emotions and stories, I think they should add a principle for communicating with teenagers: grossness.

Ooh! Maybe next time I will find some housefly clipart in the Smart Notebook gallery and use them to plot points.


  1. I think one of the things I really like about your blog and your teaching is that you seem to "get" your students. I find that many faculty in my school either were never teenagers themselves or have forgotten what its like. They're disconnected. This little idea of yours is fantastic, I'm sure it resonated with the kids. As teachers I think its important to understand what its like to be a student like Samjshah did when he shadowed a student.

  2. The Amazon review says the letters almost spell success. Too bad grossness doesn't start with that missing s. The story the review mentions sure has its own grossness factor.

    I'm probably guilty of forgetting what it was like, or of never having been at all like your usual teenager. Hmm, I'll try to keep that thought running around in the back of my head too.

    I teach college, but one of my college courses (trig, in fact!) is mostly taken by high school students. Good stuff to think about...

  3. This "urinal fly" technique of focusing does tell many that we as human has attention span. Having something to focus on, at least address the issue of losing focus and attention in the classroom too. Probably we should, as teacher, stick a "whiteboard fly" somewhere on the whiteboard to grap the most-needed attention.

  4. Before we get too deep, let's remember that boys and men like to use urination as an opportunity for target practice. I don't know that that the urinal fly says much about humans, though it tells us something about males :-)

  5. I'm not sure I'd go so far to draw conclusions about attention span, either. (But it's an interesting theory.) More like it's much easier to get somewhere when you have a predetermined destination.

  6. This goes great with the apocryphal Descartes and the fly story :)


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