Only January 1 and 1998 NCTM is already being saucy!

Looking forward to a #TechFreeJanuary in the classroom to start the new year (with exception for Data Science which was largely tech free up to now). #ITeachMath #mtbos

"Iterating Linear Functions—An Introduction to Dynamical Systems" 1997 Jonathan Choate and (edited by) @hpicciotto.bsky.social If students are going to understand machine learning, they should start with iteration and fundamentals of dynamical systems. #MathEdPaperOfTheWeek #mtbos #ITeachMath

I gave a talk in 2024 called "Sensitive Dependence on Initial Conditions: How AI Predictably Fails Unpredictably". A dope title! jedediyah.github.io/aapt2024/ In examples of AI failing where we shouldn't be using AI, I highlighted a behavior nobody should be surprised by: AI encouraging suicide.

another robot highlight for 2025: man wearing humanoid mocap suit kicks himself in the balls

In #MathsToday we did one of my favorite activities: Regression by Hand. Our goal is to model the bounce height h_bounce of a bouncy ball dropped from height h_drop. #mtbos #ITeachMath

Clay letters from ancient Mesopotamia are alive with idiom, sayings, and everyday language that I love. Here are just a few random ones so you can enjoy them too.

In #MathsToday we are playing and analyzing Hexapawn as an introduction to machine learning. You can play and have a machine play itself here: jedediyah.github.io/hexapawn/ There are two problem sets here: williams-bhs.github.io/docs/hexapaw...

I am a proud recipient of this year's MTLT Outstanding Reviewer award! So that's nice.

"AI tools that result in discrimination based on race, gender, age, or disability" So... basically any AI, right?

A now well-known-ish open conjecture! One reason that the tetrahedron problem is tougher is that the triangle inequality on each side is necessary but NOT sufficient. To see a deeper reason for the difficulty, the condition on a tetrahedron involves the en.wikipedia.org/wiki/Cayley%... #iTeachMath

A classic probability problem: Given a stick broken randomly at two places, what is the probability that a triangle can be formed by the three pieces. There are various proofs of the answer, but we used this last week to demonstrate Monte Carlo approaches to finding probability distributions.

The @internetofbugs.com videos are always good. Doing the work of simple fact checking of AI hype. "Unlike the SciShow team, I'm just one guy, and it certainly doesn't help when the channels like SciShow that do have the resources to make things better, choose to make things worse instead."

[New Post] Ontario Math Links - My favourite #math related links from this week: ontariomath.blogspot.com/2025/11/math... Links and help from @davidporas.bsky.social @howiehua.bsky.social @infobeautiful.bsky.social @jedediyah.com and more #MathChat #MTBoS #iTeachMath

Shared a Thanksgiving gift with my data science students today! I spend a couple months collecting used copies. Next month we will read chapter 3 Arms Race and reflect on feedback systems and the susceptibility and sensitivity of data models to manipulation.

Last week we worked on combinatorics and I asked about the weight of a binary word. In #MathsToday we worked on random walks and I asked what is the probability of ending where we started. Some of the students used the weight solution to find the probability! 🥳 #mtbos #ITeachMath

"Have you ever been a reader? I think I want to try to be a reader. I might get some books this weekend." Overheard today 📖

In #MathsToday we rolled a lot of dice and found estimates of probability mass functions for sums of n=2,3 4 dice. In #MathsNextWeek we start to explore broken stick problems! Draft of next week's guide: williams-bhs.github.io/docs/Broken_...

In #MathsToday, we saw some amazing and diverse approaches to this problem: Using the optimal strategy in "Guess my number from 1 to 100" (where we get feedback "higher" or "lower"), what is the average number of guesses it will take as more games are played?

In #MathsToday we played with the "Cat Machine" and talked about theoretical probabilities, experimental probability, and confidence in our experimental probabilities.

I have two books by an author, Keh-Gong Shih, pub in 1996 that are just brilliant! But they are definitely lost. The first is PIctorial Mathematics: Patterns. It is fabulous! full of images like this. He created his own software called Mathgraf which is used to generate the images. #mathart #mtbos

Here’s video of federal agents doing a drive by pepper spraying that hit a father and his one-year old on Saturday when the Feds were hitting Little Village and Cicero

I wrote about shallow, vague, fuzzy definitions of "conceptual understanding" and a better way to think about it. pershmail.substack.com/p/understand...

Was really curious to see how these problems would go over in #MathsToday. It was great! We talked about how to map all of the problems onto the last problem and the usefulness of knowing "how to solve it" when we can recognize and abstract problems to known strategies.

In #MathsToday, we looked at Towers of Hanoi, then asked about the optimal number of moves given n towers with k disks. Our theme is limitations of mathematics, i.e., the difference between the 2 body problem and the 3 body problem isn't just 1 more body. williams-bhs.github.io/slides/combi...

I once gave a talk called "AI is not what you think it is unless you think it is hot garbage" I've just enjoyed and highly recommend @chrissimon.au's "AI is a hype-fuelled dumpster fire that will burn down the planet and get you thrown in jail" www.youtube.com/watch?v=0bF_...

November is here, and so is the next Calendar of problems! Enjoy these with your students or for yourself, share your thinking here or on the post. #MTBoS #iTeachMath #T3Learns #MathSky #RecreationalMath #MathsToday karendcampe.wordpress.com/2025/11/01/n...

Does a copy of this report exist somewhere? "Discrete Mathematics and the Secondary Mathematics Curriculum" 1990 eric.ed.gov?id=ED325367 #Mtbos #ITeachMath

Does a copy of this report exist somewhere? "Discrete Mathematics and the Secondary Mathematics Curriculum" 1990 eric.ed.gov?id=ED325367 #Mtbos #ITeachMath

Hello #iTeachMath friends! If you're attending ATMNE New England conference this week, come to hear me & @sneffleupagus.bsky.social present on "Building Community thru K-12 Math Routines" Shelby's a wee bit taller than me so I made her sit for this photo. #MTBoS @atmnemath.bsky.social

In #MathsToday, trying to talk about state machines without talking about state machines. Also debated with students whether we should fully represent all 12 states or reduce the number of bits to the minimum required (depending on number of states used).

In #MathsToday we continued working on our graph theory exercises.

In #MathsToday we are working on graphs, and getting some motivation for our next unit on combinatorics.

Danya was one of my favorite people. He was particularly famous in the chess world for being exceedingly kind. That's a good thing to be famous for.

How many classes today were canceled because a whole suite of EdTech services are built atop AWS? You know what platform never crashes?

"Discrete mathematics in primary and secondary schools in the United States" 2004 DeBellis Valerie A. & Joseph G. Rosenstein There are some fire quotes in this #MathEdPaperOfTheWeek #mtbos #iteachmath link.springer.com/article/10.1...

new @cshor.org pset 🏃💨 drive.google.com/file/d/1NaXQ... screenshots of PDF pages 1, 2, 3, and 10 below cc #iTeachMath ♾️ bcc #MathSky 🧮

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Just realized that #NCTMatl25 was the 10th anniversary of my first NCTM conference. I had started teaching in 2006, mostly Astronomy and Physics, so it is not super weird that I didn't know about NCTM for so long, but it is too bad that more classroom teachers aren't involved (a common criticism).

Two things from #NCTMatl25 that I'm going to be using *this* week: Gail Burrill's algebra problem, and @gwaddell.bsky.social and Ed Keppelmann's 4 pile Nim.

Interactive slides! jedediyah.github.io/nctm2025/

Getting pumped to present at @NCTM.org 2025! Come to an awesome workshop on "Mathematics for Machine Learning and Artificial Intelligence". We'll play with dynamical systems and filters, feature engineer some classifiers, and talk about how not to AI. #NCTM2025 #NCTMATL25 #mtbos #IteachMath #NCTM

Idk where I adapted / stole this from, but it is this week's problem of. #mtbos #ITeachMath

[digging through my twittxr archives] do you want non-routine quadratic problems? here are 20 💌: www.desmos.com/calculator/d... cc. #iTeachMath #MathSky #EduSky #AlgebraSky

Getting pumped to present at @NCTM.org 2025! Come to an awesome workshop on "Mathematics for Machine Learning and Artificial Intelligence". We'll play with dynamical systems and filters, feature engineer some classifiers, and talk about how not to AI. #NCTM2025 #NCTMATL25 #mtbos #IteachMath #NCTM

In #MathsToday we reached the topic I've been waiting for in Data Science, Dynamical Systems. Highlighted Robert L. Devaney: www.youtube.com/watch?v=TVfn... Referenced the outstanding book/course from @stevenstrogatz.com on Nonlinear Dynamics and Chaos. Connected back to our reading of Poincaré

We reviewed this question in #MathsToday. Many of my students who have already completed AP Calc BC came up with really interesting wrong approaches to d!

Just added to my @NCTM.org yearbook collection. General "computing" had a lot of interesting overlap with current rhetoric around "AI". First glance: historically interesting, still relevant, with some pretty spicy takes mid-book!

Or, hear me out, we choose not to volunteer our students as experimental subjects without their consent for the benefit of tech companies and surveillance capitalism.

In #MathsToday we worked on set theory. Some resources came from: @draustinmaths.com www.draustinmaths.com/set-notation... And some of the exercises were pulled from @oscarlevin.com's Discrete Math (3rd edition) discrete.openmathbooks.org/dmoi3/sec_in...