The Yellow Pages Are My PLC

This is a total gamechanger:

If I call a business or a government agency and represent myself as a math teacher who is curious about their work, they will spend a not-insignificant amount of time answering any question I have.

I’m 100% so far on, like, six attempts. I don’t know why I never tried this before.


Running list of examples that have made it to this blog:

  1. [WCYDWT] Pure Performance. I wanted to know the speed of the car in the video so I e-mailed the agency representing the director who then put me in touch with the visual effects supervisor.
  2. [It Got Away] Vermont License Plates. I called the Vermont DMV and received a trove of information about license plate issuance, including the combinations of letters they don’t allow.
  3. [It Got Away] Ladder Spreaders. I called Werner Ladder Co. and spoke to an engineer who gave me the skinny on ladder construction.
  4. Partial Product. The corporate grocery store told me no way that’d let me take photos on their counter so I head over to the local grocery store on the corner where the grocer, after we worked through our language barrier, let me set up my problem.
  5. Guggenheim. I called the Guggenheim’s public relations department, told them I thought Hans Peter Feldman’s exhibit was an excellent application of math and I wanted my students to experience it. I asked them for the blueprints to that room and they sent them. They told me I couldn’t pass them around, though, a request I’ll honor even though it bums me out.
I'm Dan and this is my blog. I'm a former high school math teacher and current head of teaching at Desmos. He / him. More here.


  1. I think there is a certain amount of respect that “math teacher” carries with it, and of course people naturally have a positive response to someone who is interested in what they do. I’m glad this is so effective!

  2. This is very intriguing, especially after a recent email thread I’ve been on where teachers were throwing their hands up in the air and dismissing students’ questions of, “When am I going to use this?” (Which drove me nuts.)

    Keep us posted.

  3. It doesn’t just work with “maths teacher,” you know. Even “I’m unemployed and want to know what it’s like working for your company” is almost always answered kindly.

    I was on course once with about a dozen long-term unemployed, and we all managed to arrange a *half-hour interview* at the company of our choice with just polite words, and at most two attempts.

    I think in the end, people quite like talking about their jobs. And helping the curious.

  4. *grin* Hallelujah! I’m an electronics tech (now electronics teacher) and I spent a non-insignificant amount of my career trying to get math (and other high school) teachers to listen to me. I could see that incoming employees (and vocational school interns) were underprepared in math. Or more to the point — “malprepared.” They usually could not judge whether a particular mathematical approach to an electronics problem was sensible… they couldn’t even judge if the answer was sensible. Worse, their deeply-ingrained need to “put it in transformational form” actually *distracted* them from other focus points — things like, is the underwater camera going to crash into the ocean floor? Are the fish at the edges of the photo being measured as accurately as the fish in the center? How bad is the distortion, and can we live with that? Will our current underwater microphone work for recording a new species of whales talking? (answers: no, no, yes, and no).

    It took longer to unteach them distorted ways of thinking than it would have taken to teach them to solve the problem. They showed all the classic symptoms of pseudocontext poisoning: feeling “lost in space” when old skills are wrapped in new problems; being uncritical or sometimes completely unaware of the process of problem-solving; not being able to judge whether yesterday’s problem-solving approach is relevant to today’s problem.

    I only wish I had had a pipeline to math teachers back then. Good luck with your cold calls, and if I may suggest it, it might be worth approaching your local vocational school (and/or engineering school). Teaching at a vocational school is like a treasure trove of context, and faculty there are likely highly motivated to help you provide them with better-prepared students. Plus, if they’re like us, they have shops full of machines, tools, and robots. :) Thanks for the great blog!

  5. Just wanted to add that maybe you didn’t think of it because you always had a lot to do during business hours before…

  6. This cracks me up. Wasn’t there another WCYDWT where you called a company and they bent over backwards for you? It’s on the tip of my tongue….maybe the parking meter thing? Who knows.

    I love this. And I love that you have six attempts under your belt. Many “normal” people would stop after one and feel pretty good about life.

  7. Yes . . . please post on the fruits of these phone calls. Josh G mentions that teachers ignore questions “When are we going to use this” Many times my answer, sadly, is . . . “to get you ready for, the ACT, SAT, college Algebra or Calculus.” This is not a very satisfying answer for me or my students. Honestly, where is factoring the polynomial in many ways useful besides the ACT, SAT, or other state and federal exams. Most of my students are not going to be professional mathematicians. They are going to be doctors, nurses, farmers, ranchers, home owners. All of these things involve high levels of math competence. It frustrates me to teach some of the concepts I teach without the real answer of why. Maybe I am way off base here, but we including me in the math teaching world need to do some serious sole searching. Thank goodness that Dan is getting the ball rolling and keeping it rolling. Great post, Dan!!!!

  8. So true!

    My favorite example is getting the police department to tell me how they figure out how fast a speeding car was going from the length of the car’s skid marks. (Saw the formula in a textbook and wanted to verify it to see if it was pseudo context or not…)

    Or for the same police department to give me statistics on ANYTHING involving drinking and driving. It was a way that I could tie my math class legitimately to the character education course the school was running.

  9. Alby — that’s what I’m discovering…

    Sue, I just started teaching 51 weeks ago :) so until a month back, I did absolutely nothing but run from the classroom to the electronics shop to my office (trying to plan interesting content for tomorrow), then sleep. Now that I’ve discovered the blogosphere, I don’t sleep anymore (curse you Dan!). No blog (I’ll write to you via yours).

  10. My school library used to have a book for Math called something like “where will I ever use this” but it went walkabout. I’ve tried finding a site on the net that might be as useful and although this one is interesting it’s not as good as the book was. Does anyone have any other sites that could be as useful?


  11. The reason they will talk to you for a not insignificant amount of time is because they are eager to share with someone that is outside of their business that has an interest. I made a similar revelation with graduate students doing research. They were all very eager to share what they were researching and what they have learned so far.

  12. This also works in ed research too. I’ve emailed at least a dozen different professors asking for copies of journal articles that would normally cost me something ridiculous. All but 1 have emailed me back promptly with a pdf and most are willing to answer questions and talk implementation or implications. Well, except for a few guys in Israel who only had them in Hebrew but they were kind enough to provide me with the overview.