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If this arrow isn’t in the new math teacher’s quiver, it oughtta be.

How do you answer the question: when will we use [x] in real life?, where [x] is some abstract concept or, as in my case, the 97% of math that doesn’t explicitly involve “shapes.” I have witnessed and, myself, promoted answers snarky and serious, long and short. You oughtta have something.

Motivating Question

  • When will we use [y] in real life?, where [y] is the abstract corners of the course you teach?

Optional Viewing

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. My grade 11 math teacher’s answer to my question “When will I use this in my life?” was, “If you need to ask that question you don’t belong in this class.” So I left.
    This is the same teacher who had the “Vegetable Row”. After every test he rearranged the class from top mark to bottom. Lowest marks sat in the row by the door. Guess which row he taught to. That was 1978.
    Amazing. I actually love teaching math now. And I am always listening for “when will I use [x]?”. The first part of my answer is always, “That’s a great question, I’m glad you asked.” The rest isn’t aways satisfying, but it least the question and the questioner aren’t dismissed.

  2. Congrats on getting married, Dan. Yeah, I brought it up on your blog.

    It’s out there now. Yep, bloggers, he’s off the market.

  3. @Jan: Interesting. Rearranging seats from top score to low score. If you think about it, that is pretty much how life works. It is how schools will always work. Best teachers get the best classrooms and get to teach all the AP classes and honors classes. Worst teachers get stuck in the basement teaching remedial freshman. However, in the classroom with students it is kind of funny. Teachers always teach to their favorites. This teacher only picked the top students as his favorites. I doubt any of the backrow crew is in therapy over it.

    @Ryan: What breaking news are you going to update on next. Dan was far from secretive about his wedding.

  4. Ooooh, claws out in the comments!

    This is going to sound pretentious as hell, but my goal is to teach in a way that it doesn’t occur to them to ask. (Problem-based instruction, where they are inventing the math they need.) I don’t think math necessarily has to be useful to be fun and beautiful, and I try to communicate that attitude.

    I’m not perfect, it does come up — I usually take it as a sign of boredom and frustration, and change the angle of attack, or ask a different question, or do something else for a while.

  5. @ Mike: I tried to think of real-world examples of people being publicly ranked and paraded based on achievement–I came up with elections and sports competitions, both of which are voluntary activities. Seems to me schools won’t always work that way, because it doesn’t work.

  6. I think Kate nails it. Both the idea math doesn’t need to be useful to be fun and beautiful, and the reading of the question as a sign of boredom or frustration, emotions that are usually better addressed in other ways than by providing some smart rationale for the subject.