Reposted
Cool! The circles in an Apollonian Gasket can all have an equation of the form (n|x|-a)² + (n|y|-b)² = 1, where n is a positive integer, and a & b are non-negative integers < n. www.desmos.com/calculator/6...
#MathSky #iTeachMath
#MathSky #iTeachMath
Apollonian Gasket
www.desmos.com
December 28, 2025 at 9:13 PM
Cool! The circles in an Apollonian Gasket can all have an equation of the form (n|x|-a)² + (n|y|-b)² = 1, where n is a positive integer, and a & b are non-negative integers < n. www.desmos.com/calculator/6...
#MathSky #iTeachMath
#MathSky #iTeachMath
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As pointed out by @paulakrieg.bsky.social and noted by @mpershan.bsky.social, longtime #mtbos partner and collaborator Malke Rosenfeld passed away last year. She investigated and taught the mind-body math connection, engaging hundreds of teachers and learners in #mathart - dance! RIP great friend!
December 31, 2025 at 3:27 PM
As pointed out by @paulakrieg.bsky.social and noted by @mpershan.bsky.social, longtime #mtbos partner and collaborator Malke Rosenfeld passed away last year. She investigated and taught the mind-body math connection, engaging hundreds of teachers and learners in #mathart - dance! RIP great friend!
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This quiet week is for art. Sharing daily something marvelous I've seen.
First up: Oliafur Eliason at the Hirschhorn.
One light source, one rotating crystal ring, a white wall. That is all.
First up: Oliafur Eliason at the Hirschhorn.
One light source, one rotating crystal ring, a white wall. That is all.
December 29, 2025 at 2:03 PM
This quiet week is for art. Sharing daily something marvelous I've seen.
First up: Oliafur Eliason at the Hirschhorn.
One light source, one rotating crystal ring, a white wall. That is all.
First up: Oliafur Eliason at the Hirschhorn.
One light source, one rotating crystal ring, a white wall. That is all.
Reposted
Look what I made!
December 25, 2025 at 10:16 PM
Look what I made!
Reposted
It's done! And ahead of schedule... (for once!)
A fully revised 2026 version of the Risps PDF eBook is now available for free, from
www.risps.co.uk
and from Payhip.
payhip.com/b/RGKPF
An early Ch-risp-mas present?
With best wishes of the season,
Jonny
A fully revised 2026 version of the Risps PDF eBook is now available for free, from
www.risps.co.uk
and from Payhip.
payhip.com/b/RGKPF
An early Ch-risp-mas present?
With best wishes of the season,
Jonny
December 19, 2025 at 10:16 AM
It's done! And ahead of schedule... (for once!)
A fully revised 2026 version of the Risps PDF eBook is now available for free, from
www.risps.co.uk
and from Payhip.
payhip.com/b/RGKPF
An early Ch-risp-mas present?
With best wishes of the season,
Jonny
A fully revised 2026 version of the Risps PDF eBook is now available for free, from
www.risps.co.uk
and from Payhip.
payhip.com/b/RGKPF
An early Ch-risp-mas present?
With best wishes of the season,
Jonny
Reposted
Meditate on the sweep of a spacefilling curve as a mandala.
December 11, 2025 at 5:14 PM
Meditate on the sweep of a spacefilling curve as a mandala.
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Made a site comparing the sizes of living things :)
The great Julius Csotonyi spent 5 months painting over 60 illustrations for the site, no ai used
> neal.fun/size-of-life/
The great Julius Csotonyi spent 5 months painting over 60 illustrations for the site, no ai used
> neal.fun/size-of-life/
December 10, 2025 at 4:03 PM
Made a site comparing the sizes of living things :)
The great Julius Csotonyi spent 5 months painting over 60 illustrations for the site, no ai used
> neal.fun/size-of-life/
The great Julius Csotonyi spent 5 months painting over 60 illustrations for the site, no ai used
> neal.fun/size-of-life/
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My new book is now available for preorder and I’m pretty psyched. Writing this book has been a passion project and a joy (and how lucky am I to be able to say that). It’s not due out until late spring/summer but seeing it online is really exciting for me.
Letters to a New Teacher: Real Advice and Practical Strategies for Getting Started in Elementary Teaching
Amazon.com: Letters to a New Teacher: Real Advice and Practical Strategies for Getting Started in Elementary Teaching: 9781032991078: Orr, Jennifer: Books
www.amazon.com
December 9, 2025 at 10:51 PM
My new book is now available for preorder and I’m pretty psyched. Writing this book has been a passion project and a joy (and how lucky am I to be able to say that). It’s not due out until late spring/summer but seeing it online is really exciting for me.
I never public speak. But I’m going to be speaking at a conference I’ve gone to many times and have enjoyed for high school math teachers, in North Carolina. It’s late February.
tcm.ncssm.edu
I’d love to see fun math teachers there!
#mtbos
tcm.ncssm.edu
I’d love to see fun math teachers there!
#mtbos
TCM Conference
2026 Teaching Contemporary Mathematics Conference
February 27 -28, 2026
North Carolina School of Science and Mathematics, Durham Campus
tcm.ncssm.edu
December 10, 2025 at 12:38 AM
I never public speak. But I’m going to be speaking at a conference I’ve gone to many times and have enjoyed for high school math teachers, in North Carolina. It’s late February.
tcm.ncssm.edu
I’d love to see fun math teachers there!
#mtbos
tcm.ncssm.edu
I’d love to see fun math teachers there!
#mtbos
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Wow the word bocconcini has a lot of letters. It would be great fuel for one of those combinatorics problems.
December 8, 2025 at 8:07 AM
Wow the word bocconcini has a lot of letters. It would be great fuel for one of those combinatorics problems.
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I'm hooked on Hitomezashi too. I've even used it to mend something (coded in Turtlestitch and machine embroidered) and I've also experimented with patterns from recurring decimals. Have fun!
December 6, 2025 at 8:02 PM
I'm hooked on Hitomezashi too. I've even used it to mend something (coded in Turtlestitch and machine embroidered) and I've also experimented with patterns from recurring decimals. Have fun!
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The Journal of Mathematics and the Arts invites applications for Editor-in-Chief from scholars who understand that mathematics and art are not separate worlds. Help us showcase research that reveals the mathematical soul of creativity.
spr.ly/63321AhlWd
spr.ly/63321AhlWd
November 5, 2025 at 1:50 PM
The Journal of Mathematics and the Arts invites applications for Editor-in-Chief from scholars who understand that mathematics and art are not separate worlds. Help us showcase research that reveals the mathematical soul of creativity.
spr.ly/63321AhlWd
spr.ly/63321AhlWd
@mathskath.bsky.social
Guess what came in the mail today?!? I flipped through it and I’m already in love! 🥰
Guess what came in the mail today?!? I flipped through it and I’m already in love! 🥰
December 5, 2025 at 9:50 PM
@mathskath.bsky.social
Guess what came in the mail today?!? I flipped through it and I’m already in love! 🥰
Guess what came in the mail today?!? I flipped through it and I’m already in love! 🥰
Reposted
I learned this folding technique yesterday, so I had to make something with it.
November 30, 2025 at 4:39 PM
I learned this folding technique yesterday, so I had to make something with it.
Reposted
εεεεδεεεεδεεεεδεεεεδ...
Every four ε, there is a δ.
Every four ε, there is a δ.
November 30, 2025 at 1:28 AM
εεεεδεεεεδεεεεδεεεεδ...
Every four ε, there is a δ.
Every four ε, there is a δ.
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non-Euclidean geometry proofs where the two columns eventually meet 💡
November 30, 2025 at 1:31 AM
non-Euclidean geometry proofs where the two columns eventually meet 💡
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lotta math classes teach about completing the square without ever asking why the square felt incomplete in the first place 😔
November 30, 2025 at 1:34 AM
lotta math classes teach about completing the square without ever asking why the square felt incomplete in the first place 😔
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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
notes.mathforge.org/notes/publis...
Give it a moment to load ... there's a *lot* of them!
#GeometryPuzzles #UKMathsChat #mathsky
Puzzle Gallery in Notes
notes.mathforge.org
November 16, 2025 at 6:24 PM
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
notes.mathforge.org/notes/publis...
Give it a moment to load ... there's a *lot* of them!
#GeometryPuzzles #UKMathsChat #mathsky
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We're disappointed to see Ben Barres's powerful book "The Autobiography of a Transgender Scientist" among the ~400 titles removed from the Naval Academy Library. Needless to say, we're proud to have published his book and will keep it — and his memory — alive.
The Coming Out of a Transgender Scientist
"I know that I am making the right decision because whenever I think about changing my gender role, I am flooded with feelings of relief."
thereader.mitpress.mit.edu
April 8, 2025 at 8:24 PM
We're disappointed to see Ben Barres's powerful book "The Autobiography of a Transgender Scientist" among the ~400 titles removed from the Naval Academy Library. Needless to say, we're proud to have published his book and will keep it — and his memory — alive.
Reposted
Giant cardioid: version 2.5. Version 1.0 was made using Pex tubing and grommet tape. Version 2.0 was made from laser-cut pieces. The wood was too fragile, and it broke during construction. In version 2.5, I made the pieces wider and I used thicker wood. Success, I'd say! The diameter is about 5 ft.
November 9, 2025 at 4:34 PM
Giant cardioid: version 2.5. Version 1.0 was made using Pex tubing and grommet tape. Version 2.0 was made from laser-cut pieces. The wood was too fragile, and it broke during construction. In version 2.5, I made the pieces wider and I used thicker wood. Success, I'd say! The diameter is about 5 ft.
Reposted
Understanding geometry through model making
November 6, 2025 at 5:51 PM
Understanding geometry through model making
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Hi Blue Sky! I edit the Journal of Humanistic Mathematics. We publish articles, essays, #fiction & #poetry on doing, teaching & living of #mathematics. So far we had more than 850K full-text downloads of our content - why not check us out? scholarship.claremont.edu/jhm/ #math #openaccess #mathart
Journal of Humanistic Mathematics - an online-only, open access, peer reviewed journal | Current Journals | Claremont Colleges
Journal of Humanistic Mathematics - an online-only, open access, peer reviewed journal published by the Claremont Colleges Library.
scholarship.claremont.edu
September 30, 2025 at 4:42 PM
Hi Blue Sky! I edit the Journal of Humanistic Mathematics. We publish articles, essays, #fiction & #poetry on doing, teaching & living of #mathematics. So far we had more than 850K full-text downloads of our content - why not check us out? scholarship.claremont.edu/jhm/ #math #openaccess #mathart
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Reposted
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
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
October 29, 2025 at 3:38 PM
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
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