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. dy/dan post #2314 I’m going to keep in my back pocket for the classroom – the kids are going to flip their s#%t over this. Thank you!

  2. These videos are phenomenal. I particularly enjoyed the episodes about how the teaching profession has bettered you as a person. I can attest to that! How much time does it take for you to create an episode?

  3. I really should’ve had an FAQ or a colophon or something up by now given how often this question crops up, but at least I’ve got Bill cleaning up after me until then.

  4. Dan – stated tongue-in-cheek and with a healthy dose of self-irony this goes some way. To be difficult, though, what about similarly vacuously true statements such as
    – spelling is all around us?
    – chemistry is all around us?
    – economics is all around us?
    – power struggles are all around us?
    – poetry is all around us?
    Why don’t the kids ask “when will we be using this” in arts class? Do we really think that applicability and utility – or ubiquity – are students’ primary criteria for finding school subjects interesting or less so?

    While I am not aware of research on what it takes to get students excited about math, a lot of work has been done on understanding students’ attitudes toward science and technology. Svein Sjøberg, one of the originators of the ROSE (Relevance of Science Education) project, writes that

    It is a paradox that the most S&T-driven economies in the world are experiencing a lack of interest in S&T studies and careers. … young people do not choose their studies or careers because it is good for the domestic economy. Instead, they base their choices … on their own interests, values and priorities. … The lack of interest in S&T is not only a problem for the economy, but also a threat to democracy, as … a scientifically illiterate voting population can be easily manipulated by propaganda.

    … there are dramatic differences between the responses from students in rich and in developing countries. In developing countries, students have a strong desire to become scientists, whereas students in most OECD countries are reluctant …
    From How do students perceive science and technology? in Digital Divide Network

    With this starting point, Sjøberg and others have taken an empirical approach to what aspects of and approaches to science might spark students’ interests, and by now the answers go well beyond reminding students that “science is all around us!” What approach to math would help students find it engaging? I suspect that your efforts at reducing frustration by permitting students to retest may make more of a difference than any philosophizing about math being everywhere. Real world applications have their place, but they’re only a part.

  5. ‘Cause, like, ah, ah, ah, if this, ah, video, and you, like, yeah, you, ain’t up on, like, you know, ah, ah, ah, up on, yup, that one, the TED thing, ah, like on that TED stage thing, doing a ah, ah, um, ah, like, ah, ah, ah like a 20 min video snack of, ah, mmm, well, you know, yup, that math thing — yup, the one where math or something is like, ah, everywhere, with a bit of, ah, Adobe cool-er-ific Effects tossed like in it — well, ah, ah, um, then like TED (and all dem, ah, did you catch this TED thing I just ah, like saw, types) ain’t cool and ah, like I’m thinking about like quitting teaching or something just to sweep, ah, like, ah, ah, ah like all around your classroom door every morning ’cause like here’s the thing:

    of all like these video like things you’ve ah, ah, ah gone and made or something, this is the first, ah, (can I say that?) well, it is, IMHO, yup, its the first one that actually pushed beyond the obvious (beyond what is um, ah, ah, ah, on video and all, which is still like, um, magic to like most of us) and kicked ah, ah, like, ah the whole mother down.

    Sure, topics like ah time and why ah, ah, ah being a teacher has like changed how we be like humans and such, well, that’s cool, but this one?…

    …well, ah, ah, you see, this one has like mad deep observation skillz that go like way, way, way beyond the beyond of what most of the ah, ah, like rest of like us sorta already knew in our guts and all…and finally pulled off the ah, ah like, um….well, you know, ah, right?…like pulled off the big bam boom tour of how:

    a) subject of choice + b) vision + c) new tools (or at least somewhat new tools) and d) storytelling and e) mad crazy storyboarding/editing and f) a dose of the “now that I have their attention let me drop this bad boy on ’em” = g) something fierce and proud on any edu-Richter scale.

    In other words:

    Sweet mother of math!

    I’m feeling like Fred Sanford, grabbing my chest, telling Elizabeth that I’m comin’ home!

    Or at least figuring out if English can be just as cool, before I fully switch over to ah, ah, ah, like the math side of the school building. (wink)

  6. H, thanks for your thoughts here and for the clarifying nod in Kate’s direction in the preview post. In reply:

    I’m not affirming the cliché “math is everywhere,” where you’re encountering math in grocery prices or car mileage or whatever. I’m trying to re-cast it as a literal, visible thing, where you open your eyes and it’s impossible to dismiss the calculus, impossible to ignore the possibilities.

    The problem with “why does math need to be applicable? it’s fun!” is that fun is subjective. Art doesn’t get that question, but art still isn’t fun for every student.

    After reading some Papert over my honeymoon (dork!) I like the idea of math as a satisfying act of creation more than either of our theses. Mine is intangible. Yours is subjective. I want to show my students some interesting habits of the mind this math stuff leads to.

    More next (or maybe next next) post.

    @Christian, not sure what that initial parody was about but thanks for the props. Feel free to, uh, share this one along if you feel really compelled.

    This was the longest production time of any episode to date and the views are way beneath any of the others in their second day. I don’t understand you people at all.

  7. Color me compelled.

    Oh, and undoubtedly compelled enough to use this vid as a key example during our opening faculty meetings now that I’ve been asked to speak to the entire campus (preK-12) about something that is grabbing my digital eye, something that is particularly ripe for the picking on behalf of our kiddos (where it matters most).

    I have no doubt that the irony of an English teacher lauding a Math teacher will be noted…and well received.

  8. I’ll have to look up Papert – thanks for another reading suggestion. I figured Christian was making some clever fun of my being literal-minded to the point of missing the point of the video (guess I would deserve that), but I’m also too literal-minded to tell whether that really was what he was up to :) And still unsure about the balance between seriousness and humor/irony in the last lines of the video. As parody it would be hilarious, but you’d be taking the view parodied pretty seriously. Or something. I don’t know. Time to log off.

  9. I’d be interested to hear your thoughts on Papert. I just finished Mindstorms. I too loved the idea of math as creation. I’m just not sure how to bring that creation into the classroom when I have a set amount of material to get the kiddos to understand.

    And very nice work on the video(s), but you knew that. :-)

  10. I read one of his articles over my honeymoon (can’t re-find it for the life of me) and found at least 50% of it suspect, but was intrigued and challenged enough to track down anything else he’s ever written or said. Let’s host a book club sometime.

    (I have known that compulsion – to wholly devour a writer’s C.V. – exactly three other times in my life: Mike D’Angelo, David Foster Wallace, and Kilian Betlach. Nice to add a new name to the list.)

  11. Mindstorms is available here (my trusty former student aide pointed that out to me after I bought the book).

    Gary Stager has links to quite a few articles by Papert here. I haven’t started The Children’s Machine yet.

    Let the book club begin!

  12. I have just enough free time and nerdiness to join a math teacher book club. What are we reading first? There are quite a few articles on that one link from Jackie.

  13. If JackieB and Dan are together in recommended reading, I’m not missing out. Seconding Kate’s question on where this book/article club begins.

  14. I’m working on my ~2000 miles back to school. Can’t stop turning my head to watch how the different levels of scenery move.

    Not quite your point, but it’s how this video changed my life.

  15. No no no that’s exactly my point. This is the same drive you’ve seen before, only now a veil has been lifted between you and the world you live in. That’s why I love math.

  16. But nearly causing car crashes is not the point….

    Though it is the same thing after marathon prep sessions. I get up from the Geometry book and am just surrounded. Then I have to tone it down.

    So looking back at the discussion with H, I’m reunderstanding you. Any quality class changes the way I look at the world. Every class has the potential to change our experiences. Though I haven’t had that experience with spelling….

  17. Just finished watching the final episode and back-tracked to this one. And I love it for the “so what” angle above all. You reminded me of my reaction to normal life after taking a conceptual (no math-guy here) physics class in college. My mantra for the entire semester, with friends and better still to myself when alone and just watching the world go by – birds coasting, plastic bags falling from the air – was: “It’s all physics.”

    Really well-done, Dan. Beautiful.