what a final @todos-math.bsky.social e-news message! congrats to @dingleteach.blacksky.app for her leadership of TOODS as she segues into Past President; congrats to @karikokka.bsky.social as incoming President; and congrats to two incoming Directors, including Dr. Sara Rezvi! 🔗 www.todos-math.org

Algebra teachers, check out these three rational exponent problems from Bryan Anderson. See the hints and answers on Open Middle: www.openmiddle.com/rational... www.openmiddle.com/rational... www.openmiddle.com/rational...

In #mathstoday (well, actually yesterday) my Year 12s tackled another great Underground Maths problem. This one worked really well & stimulated loads of discussion, helping cement their understanding of logs. Definitely recommend 👍🏼 undergroundmathematics.org/exp-and-log/...

Any chance any of you math folks out there want to uplift one of my students? She created an instagram with a fictionalized journal of mathematician Srinivasa Ramanujan [ www.instagram.com/lucie.r.vk_e.... Personally her journal floored me! *I'd love for her to get some followers!!!*

I have a high school student who created a fictitious journal for Ramanujan for a class project, after researching his life. It's so cool, and has entries from a fictitious Ramanujan along with others. If this intrigues you, please follow&share this insta: www.instagram.com/lucie.r.vk_e... #MTBoS

A problem to start calculus class on Monday. We're not to integration yet, but I want to start nudging student thinking in that direction. Plus a bit of retrieval practice and creative thinking/problem solving. #ITeachMath

working with students on problems of the nature: How many ways can you distribute 10 cookies among 3 people if the max # per person is m? For e.g. m = 4, you can ignore m and make the full list of all distributions. Then naively cross off every entry each time it contains an entry ≥ 5. But, then+

This is so cool! Given only the "exponential minus log" function, elm(x,y)=exp(x)-ln(y), and the constant 1, you can perform +, -, x, ÷, exp, ln, trig, powers, roots, etc. You can also obtain e and π! See arxiv.org/pdf/2603.21852 and arxiv.org/src/2603.218...

I've confirmed to speak at the NCTM Annual in Denver 🗣️🎤 Here is the abstract: 🪑: www.aievolution.com/ntm2601/Abst... Deets: #NCTMDEN26 Annual Meeting, October 28-31 in Denver! www.nctm.org/denver2026/ See you there??? #iTeachMath ♾️ #MathSky 🧮

I had a student who essentially needed something to yield 0 when positive and to yield 1 (or -1) when negative. They came up with this idea 💡 which was oh so lovely. #mtbos I love creativity and out of the box thinking.

Every day in Calculus, there's a warm-up on the board as students walk in. Gets them thinking and sets the tone before we even start. A few from this week: Crack the Code, Which One Doesn't Belong?, and four trig derivatives. Low stakes, high engagement. #ITeachMath #MathsToday

I probably won’t be able to read this book (Proof: How the World Became Geometrical) for a while. But I thought the two other books by the author were great. And what a lovely cover! #mtbos

These are great questions for students to be asking as they approach a challenging math question.

At Gathering 4 Gardner, @cardcolm.bsky.social suggested I try the following 3D-printing project. Recall the "napkin ring problem": Take a sphere of radius r and drill out a hole along a diameter so the remaining shape has height h. Then the volume, V = πh³/6, does not depend on R. He thought that

Another 3D-printing suggestion from @cardcolm.bsky.social: Archimedes proved that if you slice a sphere of radius r with two planes a distance h apart, the surface area is 2πrh—the same as a cylinder of the same radius and height. So, it doesn't depend on where the slicing occurs. 1/2

I used to pride myself on writing questions that assessed what we had talked about, but in new & different ways. They'd get plenty of "the standard" questions, but I'd regularly mix in extension problems to see how they can apply their understanding. This was a favorite #mtbos #iteachmath

Small Rhombicosidodecahedron if u even care. I know it can be made with a single (incredibly long) modelling balloon because every vertex only has four lines coming from it, so it has an ✨Eulerian path✨

I wrote a blog post about my G4G16 gift. If you want a copy of your own, download and print the files!

Golly I love living in NYC. I got a ticket for this at noon today. I was filled with childlike wonder for 5 minutes of paper planes swirling down from an oculus… thewangcontemporary.org/events/20000...

Three knight's tours of a 32x32 chessboard. Each contains the set of edges (knight's moves) shown in the top left. Each is a single unicursal path that can be traced without lifting one's writing implement from the paper. #mathart

Three knight's tours of a 32x32 chessboard. Each contains the set of edges (knight's moves) shown in the top left. Each is a single unicursal path that can be traced without lifting one's writing implement from the paper. #mathart

Three knight's tours of a 32x32 chessboard. Each contains the set of edges (knight's moves) shown in the top left. Each is a single unicursal path that can be traced without lifting one's writing implement from the paper. #mathart

Three knight's tours of a 32x32 chessboard. Each contains the set of edges (knight's moves) shown in the top left. Each is a single unicursal path that can be traced without lifting one's writing implement from the paper. #mathart

Two knight's tour (32x32 and 64x64). Two terms of an infinite sequence of tours.

Built a “3D” sphere (SVG) to show RYB transformations. Over-iterated in @codepen.io 10% optimization, 90% procrastination. codepen.io/meodai/full/...

A few more experiments! Nothing new but these look nicer than my last set I think! #mathart #mtbos

This afternoon was the "Hands-On Activities" portion of the conference. I brought the supplies (150 laser-cut pieces of wood, 1000 yards of yarn, wood glue, and 50 binder clips) to make a giant cardioid and a giant nephroid. It was fun, and I think they turned out great.

This is a first attempt at categorising @catrionaagg.bsky.social 's puzzles by the techniques used to solve them. My hope is that this makes it easier to use them in class. notes.mathforge.org/notes/publis... #mathsky #UKMathsChat #ITeachMath

We were invited to read from our books, which I did of course. But first I had some opening words, which I thought I'd share with you here. I'll share video too, once that's available.

Charles O Perry sculpture in the lobby of the Hyatt Regency in San Francisco

Vector fields as art. In #MathsToday the students had to create a vector field and overlay it with a picture to create Vector Art. Just a fun little extension at the end of a unit. #iTeachMath

I was gifted a gorgeous origami sculpture of five intersecting tetrahedra. This inspired me to recreate it using Desmos. www.desmos.com/3d/m7hqyu2gpr en.wikipedia.org/wiki/Compoun... @desmos.com #iTeachMath

A tour of tours, an open knight's tour of an 99x99 chessboard. The tour starts in the bottom left corner and ends near the top right corner.

I had a productive day in #Desmos today. I also made a simulation of the refraction and internal reflection that causes rainbows. Enjoy, #EduSky and #MathSky ! #IteachPhysics Full spectrum: www.desmos.com/geometry/hga... (reverse contrast!) Single ray with angles: www.desmos.com/geometry/l32...

Six squares and a quarter circle. The blue square has area 2. What’s the yellow area? #geometrypuzzle

Last two drawing-on-the-cricut experiments -- Hitomezashi patterns! Now I’m done for the day! #mathart #mtbos

And another cool one, using the code provided here! penplotter.art/p/algorithmi... #mathart #mtbos

Finally got an hour to play with Desmos and my cricut. To my eyes, what I was able to make is stunning! 😍 🤩 #mathart #mtbos

Happy (topological) Valentines Day!

Gathering 4 Gardner is this week. I'll be running an activity where we'll make one of these giant cardioids (and a giant nephroid). Today, I'm taking advantage of the sunny, above-freezing day to laser-cut the pieces outside.

One more, which I call "I ❤️ the Cardioid." (A cardioid from one direction and a heart in the other.)

A #genuary sketch that escaped January - Bauhaus Fibonacci www.upstride.ch?id=bauhausfi... #CreativeCoding #CodeArt #genuary2026

Things have been rather busy at the #illustratingMath trimester at the Institut Henri Poincaré for the last two weeks. A number of illustration projects have been started. I'll share some highlights in this thread. (1/6)

#mathstoday started with one of my favorite early probability activities. Students write events on stickies for almost never to almost always and another group tries to sort them. Lots of discussion about wording and googling for more info.

Still playing with these impossible cylinders. Here I have an ellipse with the "Batman curve" in the reflection.

omg everybody go draw a horse this is what the internet was made for gradient.horse

A cool article reddit led me to on how to make some cool math art! penplotter.art/p/algorithmi... #mathart #mtbos

#iteachmath #mtbos What do you call it when you solve a log equation by performing the operation of making, say, 10 the base of each side? log(x+2) = 5 10^log(x+2) = 10^5 What’s the name of this operation?

This question is playing with fire.

This isn't easy to share, but I'm grateful for any support, prayers, or encouragement during this season. Love to all. www.gofundme.com/f/support-fo...