Why I Don’t Use Your Textbook

Lately I am a man obsessed. As others are obsessed by numerology, the year 2012, or the birth certificate of President-elect Obama, I am obsessed by the Rule of Least Power and how succinctly it explains why I have never found the right place for a textbook – any textbook – in my math classroom.

Whenever my mind starts to spin down for sleep, it wanders to this computer programming axiom and everything becomes hypnotizing and clear. In this waking dream, I see a spider’s web connecting disparate artifacts:

  1. my textbook;
  2. The Wire, Friday Night Lights, The Shield, and 24;
  3. What Can You Do With This?
  4. the Muji Chronotebook;
  5. and the Rule of Least Power, most crucially:

Use the least powerful language suitable for expressing information, constraints or programs on the World Wide Web. – W3, The Rule of Least Power.

And then I’m inches from some grand unification theory of curriculum design. It’s close. It’s killing me. If I could find seven contiguous hours, I might fully articulate the network and I’d finally have an operational theory, an operational aesthetic, really, putting only a few miles between me and dy/dan: algebra, volume one.

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. The rule of least power is found all over the place. Amateur Radio Operators (Ham radio) have the same guidance provided by the FCC that flows through to any type of communication I’d say:

    “At all times, transmitter power must be the minimum necessary to carry out the desired communications.”

    Fits well for volume of voice, number of powerpoint slides, and number of items on your website navigation menu!

  2. Standards have left a big mark on the packaged curriculum being peddled nowadays. Every publisher makes sure their content is aligned to a t to the national standards and I think in a lot of classrooms that’s what goes down. I like your “What Can You Do With This” posts because I think that part of what leaves an impact is space for a bit of irregularity in the classroom, and a text book is never going to package that.

    Last month I went to a “curriculum caravan” – a bunch of sales pitches for textbooks – and I heard a math coach mention to one of her math coach friends that she likes the really structured curriculum because it can basically be delivered by a machine, poorly skilled teachers could still accomplish something, she said.

    Seems like the flip-side is that highly skilled teachers sometimes also get forced into a book.

  3. @Nick: I think you point out the biggest problem with our schools’ current textbook culture. The textbook becomes a crutch- propping up those teachers who probably shouldn’t be in the classroom and making it seem as if they’re doing OK. On the flipside, those who’re ready to run and design truly effective curricula can find the system’s “need” for a textbook a hindrance.

  4. Dan, interesting connection. My difficulty right now is in applying the concept to a field where “power” isn’t defined by a number of amps, volts, watts, or ohms.

    Nick and Ben’s imprecations that textbooks – heavy-laden with adoption board-satisfying jargon and explicit standards – are good only for inexperienced teachers offer a great jump-off question for a forthcoming post:

    What kind of textbook would seasoned, veteran teachers value? And by value, I mean “cherish,” “cling to,” and “consult often”?

  5. @Nick – Have you noticed that the standardized tests, test prep materials, benchmarking and progress-monitoring software, and textbooks are all published by the same people? “Have a lot of kids scoring low on our test? Buy our textbooks!”

    That’s like trusting a pharmaceutical company to do your annual physical…

  6. Just seven hours? Maybe a bunch of readers should come and sub for you while you produce that grand unified theory :)

    Seriously, some illumination of the why and why not to follow a textbook would be very welcome.

  7. I’m having a difficult time understanding why you wouldn’t use a textbook, just for the practice problems. How would you answer people who believe in Repetitions, I had a great math teacher who always said “Repetition is the mother of all learning…”

  8. Doug, I do use it for the practice problems (though only if their difficulty is scaffolded gracefully) so perhaps I overstated my case. It seems a terrible waste, however, to disregard 90% of a textbook that costs between $60 and $100 per student.

  9. @Scott – The cycle of testing and textbook writing is nasty. Oregon just defeated a ballot measure to spend millions of dollars generating new tests to enable a new teacher performance-driven replacement to the seniority system.

    @Dan – As far as a “seasoned veteran” textbook, I think that’s a good question. Probably none of the ones sitting around, or maybe any of the books sitting around just as a bunch of bound problem sets. The bigger question of presenting the material and exploring it seems like something folks come up with on their own to avoid totally artificial, why-are-we-learning-this inducing content.

  10. Dan, I’m with you about the cost and waste of textbooks. I was encouraged when NCTM released their report recommending smaller, more focused text books. I myself piece together curriculum from different texts and stuff I’ve made up myself. But I’d love a small text of practice problems. Ava.

  11. @Dan, re: a textbook I’d “cherish:”

    I’ve mulled this over for awhile, and I think the only type of textbook that I’d “cling to” or “cherish” would be a text that I’d written- and that would probably only be because of the royalties.

    I guess I just can’t envision a single text that would be appropriate to use every day for an entire semester. I’m thinking more of science texts (my speciality) here, where generally the questions and problems in the book are simply insufficient to get at the real meat of the content.

    If I was forced hired to write a high school science textbook, it would be written in simple English, rely heavily on analogies, include only basic overviews of the content, and have a hefty list of resources (websites, non-fiction books, videos, etc.) for each section for when you need to go into more detail.

    However, I don’t what I’ve described is best suited by a physical textbook. It sounds much more like an online document.

  12. Texts are very useful for those kids who are fast readers and get content better from reading than from listing to teachers or watching videos. I know that I often have little patience for the droning of lecturers telling me stuff I picked up in the first 5 minutes of the talk by reading the paper. My son also would rather read a book on a subject than sit through a dull class. Of course, many kids are not good enough at “reading to learn” for their text books to serve as much more than backpack weights.

    That said, I rarely follow a text when I teach (mostly grad classes), because the material I teach has not been put into good books. I do provide reading assignments for those who would prefer to get the material that way.

    For math, the key learning happens by solving problems using the methods. A text is great for providing a source of well-crafted problems of graduated difficulty (now, if only the math text writers actually did that!). At the elementary-school level, the Singapore Primary Math series actually does an excellent job of providing that sort of graduated exercise, as well as supplementary books with intensive practice and challenging problems, for those who need more. At the high-school level, the Art of Problem-Solving texts have some of the best problem sets I’ve seen.

  13. Kevin, thanks for the commentary, and for the reference to Art of Problem Solving. It’s at the top of an (admittedly pretty stagnant) to-read list.