So Happy Together #5

I’m one day out of a presentation to the Oakland Teaching Fellows on digital projectors (working title: PowerPoint – Do No Harm) and really excited about it. A lot of these folks are right around my age, some older, which’ll make for different dialogue than what I’m used to in my high school classesWhich usually hovers around who can fart loudest into the speakerphone..

This last note-to-myself circles around classroom management and how much easier it is to keep a large group of students focused with a digital projector, presentation software, and wireless remote than without.

One Idea:

Classroom Management: The Triangle Offense

Like This:

Let’s say you’re in a short lecture block. If your only tools are a chalkboard/whiteboard and chalk/marker, you’re tethered to the board.

You can draw a bit, write a bit, ask questions a bit, but always at the board. If Llewelyn loses focus, you can wander to his desk, maybe ask a softball question to pull him back in, but then you’ve gotta return to the board, all while the kids farthest from you drift off.

Your classroom dot plot looks like this:

Let’s say now you have a digital projector and a wireless remote and you’ve already loaded some discussion-worthy diagrams into your presentation software. You’re mobile.

You walk to the far side of the classroom and address the board. Your focus directs theirs. You toss a question at the opposite side of the room pulling them into your locus.

Your question, the projected image, and the kid answering the question, are three vertices of a triangle inside of which classroom management is a relative non-issue, inside of which you all have really, really good focus.

It’s the triangle offense, and it’s very effective.

Previous Editions:

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 don’t have the wireless remote, but have noticed how much more I’m around the classroom since I got an LCD projector. (Which isn’t being used very well yet, another project to look forward to this summer? Next year?)

    Now my students in the back of the class keep saying, “Why are you always standing around here? Go someplace else.” Proximity really does work.

  2. I just got a wireless slate for my Smart Board, and I can’t wait to start cruising around the class and getting my own students wondering why I’m “standing around,” as Sarah so eloquently puts it.

    You’re all over it, Dan. Sure hope we can present together someday.

  3. I’d go nuts without a wireless remote. After I dropped one earlier this year and reduced its range to about 18″, I now have a backup in my supply drawer.

  4. Here’s what I love about this: tech use that does not decrease, but INCREASES physical face time with the teacher.

    Don’t think I’m getting all Norman Rockwell about this. Empirically, physical interaction is an essential component of human connection– hence, learning. Of the disappearance of this via Web 2.0, only a few are admitting the massive implications.

  5. I love these diagrams. I am in the process of getting projectors in every classroom. This is an awesome way to keep the Digital Age learner engaged in the lesson.

  6. The declutter is a huge part of it.

    It also removes a distraction between the students and the screen – when I move away from the front of the room, it’s straight up them and the screen with nothing else in between.

    Add that it never gets bumped or jostled out of alignment, and my projections look way more pro than anything else at this school.

  7. This triangulation method really works and is used in several brazilian universities with a large success.

    As pointed by Dina, face contact proportionated by this technique is priceless, and improves learning relations, focusing not only on the technology but in the professor.

    The risk is that many teachers here in Brazil tend to elaborate a so complete matherial in the PPT that don’t leave any space for their own considerations, assuming a submission role inside the classroom and loosing many of the advantages.

    These teachers are called “retroprofessores” in Portuguese, something like “projecsor” in English

  8. “The risk is that many teachers here in Brazil tend to elaborate a so complete matherial in the PPT that don’t leave any space for their own considerations.”

    Definitely. In my second year using Keynote in the classroom, I find myself deleting more than adding, removing notes & text, leaving diagrams. We talk more, I’ve found.

  9. Dan,
    I have been thinking about this post a lot since I got a Wacom Wireless Graphire pen tablet for my Mac. I keep mulling it over in my mind. You talk at length about technology needing to increase the learning that students do otherwise it is without worth. I have been teaching for 15 years and little has immediately improved my classroom management skills like being able to write on my board from anywhere in the room. I love and appreciate how well your class is planned, and I am sure that you would think me lazy and ready for retirement because I cannot plan to the minute like you do. To keep myself intellectually honest I say I am more Socratic than you. No matter. The key thing is that when I put my Bluetooth tablet together with Skitch, for under $250 I can write on the board from anywhere in the room. I can hand the board over to a student and let them try to solve a problem. I can help one student while all the others are working, but help in a way that everyone is eavesdropping on my help. I see the heads look up and follow as what used to be one learners question turns into many learners answer. When I draw the triangle of learning for other teachers they leave and ask the principal for the money to do the same thing in their classrooms. I am sure that it is not for you because it is not enough planned, but for some other reader who is less likely, able, or used to planning it is a truly transforms the effectiveness of your teaching.