The 2025 Desmos Art Contest gallery is now live 📣! Filter by feature and find your new favorite graph at desmos.com/art 🎨 #mathsky #iteachmath #mathart

Went tidepooling today. Saw the best octopus.

Sunrise over chunks of ice floating in the East River

Here's an animation of Steiner's porism, made in @desmos.com Geometry. en.wikipedia.org/wiki/Steiner... In case they are useful to anyone, this graph contains reusable Desmos functions for doing circle-inversion of points, lines and circles. www.desmos.com/geometry/xkq... #iTeachMath #MathSky

#genuary 2: 12 principles of animation. Here's some anticipation and overshoot done in a p5.strands shader. #p5 #p5v2 openprocessing.org/sketch/2838235

Born #OnThisDay in 1887 was Indian mathematician Srinivasa Ramanujan. Despite having almost no training in mathematics, he is regarded as one of the greatest mathematicians of all time. He became one of the youngest Fellows in the Royal Society's history when he was elected in 1918 at the age of 31.

Possibly a fun activity for before Winter Break: a snowflake maker in @desmos.com (By the way, this is an old graph. It would be much easier to make in the new Geometry tool, but it might be interesting to see the trig in the Graphing Calculator). #iTeachMath #MathSky www.desmos.com/calculator/c...

Ooh, the new split-view option for Chrome tabs is quite handy! lifehacker.com/tech/google-... Right now I'm typings Qs for a scaffolded math quiz into a Google Doc, with a split-view Desmos graph by its side in the same tab. Much easier than juggling separate windows with their borders and overlaps

@desmos.com This looks like it's a bug? I'll e.mail it to [email protected] too. www.desmos.com/calculator/m...

Sunrise over Queens

I haven't been very active here for several months, because I've been working on a new book. Soon I will be able to tell you about it. Is anyone out there interested?

10th-Grade Prodigy Studying Mathematics At 10th-Grade Level https://theonion.com/10th-grade-prodigy-studying-mathematics-at-10th-grade-l-1819577209/

@jeremydenk.bsky.social I just started listening to your book Every Good Boy Does Fine, and was immediately captivated by your description of listening to K364 as a boy. I was just like that (apart from the whole going on to be a virtuoso thing 😀). For me, the middle mvt of 364 did it. More so: K488

Lava erupts from Hawaii's Kilauea volcano. One of the most active volacanoes in the world has started erupting. Kilauea, on Hawaii's Big Island, is spewing large columns of lava into the air. Kilauea is one of six active volcanoes located in the Hawaiian Islands

Sunday night seems the right time to post a gallery of (I hope!) every one of Catriona's geometry puzzles. notes.mathforge.org/notes/publis... Give it a moment to load ... there's a *lot* of them! #GeometryPuzzles #UKMathsChat #mathsky

Hey all! We've got a new episode of Graph Time with Sara and Sean for you today! Sara and I were playing with some graphs and discovered a really fun way to create tons of beautiful mathematical patterns. Check out the episode: www.youtube.com/watch?v=7v0J...

An acronym to help my Geometry students, when trying to solve a problem: STACK, which stands for Similar Triangles Are Consistently Key I had suggested STATA, for "Similar Triangles Are The Answer". But then one of my students, Victor, suggested STACK. It's much better! #iTeachMath #MathSky

"Only the Sea Saw When it Sank" www.desmos.com/3d/qnjd3qwwv... #desmos #mathart #mathplay

I'll try making some simple @desmos.com art with my students today. The only "math" part of this is the geometric dilation with a list of scale factors: the rest is just drawing with the Geometry polygon tool. So, mostly fun, but some learning too! www.desmos.com/geometry/why... #iTeachMath #MathSky

Here's a Halloween-themed @desmos.com geometry activity, in case anyone is looking for one. Task: transform the black witch's hat onto the orange one. The first few screens use constructions, and the rest use coordinate transformations. classroom.amplify.com/activity/690... #iTeachMath #MathSky

The new surface-colouring option in @desmos.com 3D allows a cute way of visualizing conic sections. www.desmos.com/3d/fiv5gnltdl (The option to have translucent surfaces doesn't save with the graph itself, so needs to be re-toggled on. It's important for seeing the full curves) #MathSky #iTeachMath

Have you noticed a change of colors? 🍁 You can now define colors in the 3D calculator that depend directly on coordinates. 📝 Learn more in the Desmos Help Center: help.desmos.com/hc/en-us/art... #iteachmath #mathsky

I saw this poster in NYC, and was struck by how it (unintentionally) embodies a key tension in the philosophy of free will. We tend to be determinist when forgiving people we feel sympathy for, and libertarian when criticizing views that we dislike.

Some Halloween @desmos.com art 🎃 www.desmos.com/calculator/z... #iTeachMath #MathSky

New yardbird! Harris’s Hawks aren’t terribly uncommon but this is a first for our east Tucson yard ☀️🪶🌵

Complex function domain-colouring of roots of unity, in @desmos.com Here's the graph: www.desmos.com/3d/hadt9rebbe They recently enabled colouring a surface using functions, so far only in 3D grapher. Side-effect: allows complex domain colouring, using 3D tool as a 2D one! #iTeachMath #MathSky

Timeline palate-cleanser: some pretty geometry in @desmos.com www.desmos.com/geometry/wgp... #iTeachMath #MathSky

There's a nice article by Siobhan Roberts about the Bridges 2025 conference in Eindhoven in the NY Times. I can now say that I am in The NY Times! (A photo credit for the shot of Chaim Goodman-Strauss and Edmund Harriss,... but still!) www.nytimes.com/2025/10/10/s...

Borromean rings in @desmos.com 3D: www.desmos.com/3d/nje29p8eqp #iTeachMath #MathSky

It looks like the Wikipedia page for Mary Brunkow got created literally just this morning, after her Nobel Prize was announced. I had heard that women in academia tend to be somewhat under-represented on Wikipedia, but this is a particularly stark example. en.wikipedia.org/w/index.php?...

I just finished a new website on fractal self-replicating tiles ("reptiles") based on polyominoes, polyhexes, and polyiamonds: www.mathartfun.com/fractaldiver...

I think my geometry students will enjoy making an infinite zoom effect, using the dilation tool in @desmos.com Geometry. Here's an initial attempt. Don't stare at it for too long! 😀 www.desmos.com/geometry/x46... #iTeachMath

Lorentz attractor in @desmos.com 3D #iTeachMath www.desmos.com/3d/mnm7duxhew

Is this a new piece of Kenny Scharf graffiti on W 57th St? I walked past it this morning and don’t recall seeing it before.

Here is a @desmos.com activity about the symmetry-preserving transformations of a square, inspired by my colleague Tom Jameson. classroom.amplify.com/activity/68c... For a really great intro to how this relates to group theory, see this by @stevenstrogatz.com archive.nytimes.com/opinionator....

Making pretty patterns is fun. And it can help you to learn geometry! I made a short video about how to make a snowflake in @desmos.com Geometry. Comments and suggestions welcome! #iTeachMath ❄️ www.youtube.com/shorts/EI1RN...

Seen at the MoMA Design Store. @momanyc.bsky.social . It’s a nicely designed light, but it’s not a hexagon! #

Great to see the NYT launch another math-related puzzle, after their Numbers game got beta-tested and then dropped a couple of years ago

In a new op-ed, Cornell Tech professor Tanzeem Choudhury and postdoctoral associate Dan Adler argue for a new labelling system for AI-driven mental health tools. Read more in STAT: www.statnews.com/2025/08/20/c...

This talk by Erik Demaine was great. And I very much enjoyed the talk by Dave Richeson on the game Left, Center, Right too!

Am enjoying attending the @momath.bsky.social MOVES conference at @nyucourant.bsky.social Any other BlueSky folks here? momath.org/moves-confer...

@mathtechcoach.bsky.social I was messing around with conics and ran across your GeoGebra inscribed one. I’m curious: do you happen to know what the point H is called, and how one might prove that the tangent-to-vertex lines are concurrent there? Thanks!

Check out the replies to the post below for an ever-growing list of great resources for math teaching! #iTeachMath #MathSky

Messing around with circle inversions in the complex plane in @desmos.com. #iTeachMath #MathSky www.desmos.com/calculator/m...

I’m at @unm.edu for a camp my kid is at, and I popped into their meteorite museum. It didn’t look like much, until the amazingly knowledgeable person working there told me more. This fragment of the Murchison meteorite is 7 billion years old: the oldest object on Earth! It contains amino acids!

My "Math, Revealed" series is freely available to anyone -- no paywall! -- in the thread below.

I just now stumbled across the website of @malinc.bsky.social. It's full of really wonderful interactive pieces on math education and geometry. Thanks so much for having created such a great resource! www.malinc.se #iTeachMath #MathSky

If you want to see a truly wonderful piece of mathematical communication, check out the thread by @stevenstrogatz.com, replying to my question below. My question was in response to his article, wonderful in itself: www.nytimes.com/interactive/... A welcome reminder of good things in the world!

I was playing around with distance loci in @desmos.com. This one is sort of fun: it looks like the orange blob avoids the black dot by looping around it. #iTeachMath #MathSky www.desmos.com/calculator/k...

My latest for @nytimes.com -- please repost so your followers can see this for free. www.nytimes.com/interactive/...