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Lonely Math Teachers

Check out this lonely math teacher on Twitter:

Taylor registered her Twitter account this month. She’s brand new. She’s posted this one tweet alone. In this tweet, she’s basically tapping the Math Teacher Twitter microphone asking, “Is this thing on?” and so far the answer is “Nope.” She’s lonely. That’s bad for her and bad for us.

It’s bad for her because we could be great for her. For the right teacher, Twitter is the best ambient, low-intensity professional development and community you’ll find. Maybe Twitter isn’t as good for development or community as a high-intensity, three-year program located at your school site. But if you want to get your brain spinning on an interesting problem of practice in the amount of time it takes you to tap an app, Twitter is the only game in town. And Taylor is missing out on it.

It’s bad for us because she could be great for us. Our online communities on Twitter are as susceptible to groupthink as any other. No one knows how many interesting ways Taylor could challenge and provoke us, how many interesting ideas she has for teaching place value. We would have lost some of your favorite math teachers on Twitter if they hadn’t pushed through lengthy stretches of loneliness. Presumably, others didn’t persevere.

So we’d love to see fewer lonely math teachers on Twitter, for our sake and for theirs.

Last year, Matt Stoodle invited people to volunteer every day of the month to check the #mtbos hashtag (one route into this community) and make sure people weren’t lonely there. Great idea. I’m signed up for the 13th day of every month, but ideally, we could distribute the work across more people and across time. Ideally, we could easily distinguish the lonely math teachers from the ones who already experience community and development on Twitter, and welcome them.

I’m not the first person to want this.

So here is a website I spent a little time designing that can help you identify and welcome lonely math teachers on Twitter:

It does three things:

  • It searches several math teaching hashtags for tweets that a) haven’t yet received any replies, b) aren’t replies themselves, and c) aren’t retweets. Those people are lonely! Reply to them!
  • It puts an icon next to teachers who have fewer than 100 tweets or who registered their account in the last month. These people are especially lonely.
  • It creates a weekly tally of the five “best” welcomers on Math Teacher Twitter, where “best” is defined kind of murkily.

That’s it! As with everything else I’m up to in my life, I have no idea if this idea will work. But I love this place and the idea was actually going to bore a hole right out of my dang head if I didn’t do something with it.

BTW. Thanks to Sam Shah, Grace Chen, Matt Stoodle, and Jackie Stone for test driving the page and offering their feedback. Thanks to Denis Lantsman for help with the code.


18 Jan 22:

This Episode of “Arthur” Gets Basically Everything Right About Math

Depictions of mathematics in TV and film generally lack nuance. When Hollywood doesn’t hate math, it reveres it, genuflecting before the eccentric, generally white male weirdos taking up space in its highest echelon – your Will Huntings, your John Nashes, etc. – with little in between.

But Arthur nails the nuance in “Sue Ellen Adds It Up,” and reports three important truths about math in ten minutes.

We are all math people. (And art people!)

Sue Ellen says No one in my family is a math person.

Sue Ellen is convinced she isn’t a math person while her friend Prunella is convinced there’s no such thing as “math people.” You may have this poster on your wall already, but it’s nice to see it on children’s television. Meanwhile, Prunella is convinced that, while she and her friend are both “math people,” only Sue Ellen is an “art person.” Kudos to the show for challenging that idea also.

Informal mathematical skills complement and support formal mathematical skills.

Prunella says You were using math and just didn't realize it. It's called estimating!

Sue Ellen says that she and her family get along fine without math everywhere “except in math class.” They rely on estimating, eyeballing, and guessing-and-checking when they’re cooking, driving, shopping, and hanging pictures. Prunella tells Sue Ellen, accurately, that when Sue Ellen estimates, eyeballs, and guess-and-checks, she is doing math. Sue Ellen is unconvinced, possibly because the only math we see her do in math class involves formal calculation. (Math teachers: emphasize informal mathematical thinking!)

We need to create a need for formal mathematical skills.

Prunella says Now let's measure the space on the wall.

Sue Ellen resents her math class. She has to learn formal mathematics (like calculation) while she and her family get along great with informal mathematics (like estimation). Then she encounters a scenario that reveals the limits of her informal skills and creates the need for the formal ones.

She’s made a painting for one area of a wall and then she’s assigned a smaller area than she anticipated. She encounters the need for computation, measurement, and calculation, as she attempts to crop her painting for the given area while preserving its most important elements.

Nice! Our work as teachers and curriculum designers is to bottle those scenarios and offer them to students in ways that support their development of formal mathematical ideas and skills.

[h/t Jacob Mehr]

Watch an Expert Math Teacher Put Three Kinds of Knowledge to Work in the Same Class

Lisa Bejarano’s post Two Kinds of Simplicity offers a useful idea about teaching complex fractions, but much more interesting to me are the three kinds of knowledge she puts to work in her class.

Knowledge About Teaching

Lisa has read widely from sources online and offline and has a great memory. So when she asks herself, “How am I going to teach [x]?” she can quickly summon up all kinds of helpful posts, essays, books – even the mental recording of previous classes she’s taught on [x].

Knowledge About Students

I stopped to think about how this would work with my class.

Lisa has taught long enough and knows her students well enough that she can test each of those resources out in her head, all during the lunch break before class. You can see her swiping right and left on each of them – “Yeah, maybe this idea. Definitely not that one.” – as she sees her students in her imagination. I’m sure Lisa is open to the possibility that her flesh-and-blood students will differ in surprising and awesome ways from her mental model of those students. I wouldn’t bet against her intuition, though.

Knowledge About Math

She ultimates decides to start her precalculus students with the elementary school analog of their lesson, turning an abstract fraction division problem into a more concrete one.

Then, as her students acquaint themselves again (or in some cases for the first time) with helpful models for that division, she builds back up to the abstract version of her task.

Lisa is only able to move up and down the ladder of abstraction like this because she knows a lot of math – specifically where it builds from and towards. If she doesn’t know that math, her options for helping her students basically shrink down to “let’s solve a few together.”


I don’t know if it’s possible to practice what Lisa is doing here. It’s knowledge, the tightly connected kind you get when you spend thousands of hours in math classes, reflect on those observations, write about them, talk with other people about them, and then use them to inform what you do in another math class.

It’s possible, even easy, to spend the same number of hours without acquiring that tightly connected knowledge.

It’s something special to see it all put to use.

BTW. My guess is a lot of those knowledge connections were tightened because Lisa is a dynamite blogger. On that theme, let me recommend The Positive Effects of Blogging on Teachers, an article which does a great job describing ten reasons why teachers should think about blogging.

Free Online Courses Start Today: Mathematical Play & Mathematical Anthropology

The final two ShadowCon courses start today. They both feature awesome presenters offering important ideas, and they’re both free!

Mathematical Play
Kassia Omohundro Wedekind

Kassia’s ShadowCon talk was such a blast, integrating several different bodies of scholarship all arguing for the mathematical and social value of play. Her course has insightful readings, illustrative classroom video, and Zak Champagne and Mike Flynn as teaching assistants.


The Art of Mathematical Anthropology
Geoff Krall

Geoff has loads of experience with innovative assessments as a coach in the New Tech network of schools. In his course, he’ll help you understand what portfolio assessments offer students and how to develop them. You’ll find me in Geoff’s course as a teaching assistant.


The Bet I Made with Teachers All Around the United States Last Year

Last year, I made the same bet all around the United States with every crowd of math teachers I met:

I’ll pick a number between 1 and 100. I’ll give you ten guesses to figure out my number. And every time you guess, I’ll tell you if my number is higher or lower.

I always wagered whatever cash I had in my pocket – generally between $2 to $20. The math teachers, meanwhile, owed me nothing if they lost. I had no trouble finding people to take the other side of that wager.

Watch one of the wagers below.

I pick my number.

She first guesses 61. I’m higher.

Then 71. I’m higher.

Then 81. I’m higher.

Then 91. I’m lower. She’s got me trapped. Six guesses left.

Then 86. I’m lower. Five guesses left. I’m an injured gazelle.

Then 83. I’m lower. Between 81 and 83. Four guesses left, but she only needs one. The crowd smells blood.

Then, with a trace of sympathy in her voice, 82. The crowd thinks it’s over.

But I’m higher.

Aaaand the chase is back on, y’all!.

Tentatively now: 82.5. I’m still higher. One by one, members of the crowd are wise to my scam.

Then 82.75. I’m lower. She has one guess left.

Then 82.7. I’m higher, at 82.72.

I asked her what I’d ask any crowd of sixth graders at this point:

If I offered you the same wager again, what follow-up questions would you have for me?

“What kind of number are you picking?” she said.

My point in all of this is that math teachers have names for their numbers, much in the same way that ornithologists have names for their birds. And much in the same way that ornithologists haven’t given me a reason to care about the difference between a Woodlark and a Skylark, math teachers often fail to motivate the difference between rational numbers and integers and whole numbers and imaginary numbers and supernatural numbers.

The difference is that ornithology isn’t a course that’s required for high school graduation and university enrollment and labor market participation. Kids aren’t forced to study ornithology for twelve years of their childhood.

So I’m inviting us to ask ourselves: “Why did we invent these categories of numbers?” And if we agree that it was to more effectively communicate about numbers, we need to put students in a place where their communication suffers without those categories. If we can’t, then we should confess those categories are vanity.

Before we give students the graphic organizers and Venn diagrams and foldables designed to help them learn those categories, let’s help them understand that they were invented for a reason. Not because we have to.

There are always ways to make kids memorize disconnected, purposeless stuff.

But because we should.

Featured Comment

Via email:

Did you ever lose?

I never once lost. I was never once asked to specify the kind of number I was picking.

Me, holding up the number I wrote down in nine different cities.