iiinova — where your digital self keeps evolving

thechalkface.bsky.social @thechalkface.bsky.social · 16/05/2026

Exploring Steiner points after seeing @johnnygriffiths.bsky.social carom-maths (and the classic video from James Grime youtu.be/dAyDi1aa40E). Made it into trig optimisation & a p5js sketch: throw in more points to see if random jitter plus MST (Prim's alg) can replicate it: youtu.be/dAyDi1aa40E

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thechalkface.bsky.social @thechalkface.bsky.social · 26/04/2026

Animation showing the key features of a circle. Original code here (allows you to pause by clicking): editor.p5js.org/thechalkface...

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thechalkface.bsky.social @thechalkface.bsky.social · 11/04/2026

Been using AI to learn @autodeskfusion.bsky.social so I could design these French cleats to 3D print for invisibly attaching a mantlepiece to the wall. Feels nice and solid, but I can remove it in half a second (you know, for when you take your mantlepiece on holiday...)

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thechalkface.bsky.social @thechalkface.bsky.social · 01/04/2026

Somewhat biased questioning methods here?! And someone at this company (which as far as I can gather is a broker of brokers of insurance companies) will be proudly reporting how many people complimented them (100% of those surveyed!)

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thechalkface.bsky.social @thechalkface.bsky.social · 27/03/2026

It's that time of year again - anyone with students who can do volumes of revolution might like to calculate the volume of a creme egg from my implicit equation:

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thechalkface.bsky.social @thechalkface.bsky.social · 26/03/2026

If we create a distribution from a subset of the normal distribution, we usually lose symmetry. In this one, we can calculate the mean using improper integrals (the centre-of-mass formula turns the Gaussian integral into a simple inspection one), and we get a mean of sqrt(2/pi).

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thechalkface.bsky.social @thechalkface.bsky.social · 22/03/2026

Tip for anyone who uses Eratosthenes sieve with students to filter for primes: with lines of 21, all the early primes make nice lines (3 and 7, the sneakiest ones, are both vertical lines, and the rest are 45 degree diagonals).

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thechalkface.bsky.social @thechalkface.bsky.social · 23/01/2026

My students wanted to know if they could bring my 'sine ruler' into their A level Maths exam. Not hugely surprised that the answer was 'no', but the reason surprised me! Apparently students aren't even allowed a normal ruler! Is this common knowledge??

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thechalkface.bsky.social @thechalkface.bsky.social · 29/11/2025

Used @geogebra.org to create 3D versions of polar curves so I could print them. SOO helpful for teaching integration when you can physically see the overlapping regions and trace the shape with your finger. Increasing theta is in the z direction.

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thechalkface.bsky.social @thechalkface.bsky.social · 30/10/2025

I love breaking the unspoken rule about fraction diagrams (all pieces congruent, not just equal in area). Here are a few of my favourite non-standard representations. A one radian sector fills half the unit square, the curves y = x² and y = √x enclose 1/3 of the square. Can you come up with more?

A one-radian sector of a unit circle filling exactly half the unit square.

The curves y = x² and y = √x between x = 0 and x = 1 splitting the unit square into thirds.

Two circles that perfectly fit side by side within a larger circle, each covering a quarter of the total area, leaving behind two 'batman' shapes which must, by symmetry, also cover 1/4 of the total area.

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thechalkface.bsky.social @thechalkface.bsky.social · 08/10/2025

Quite pleased with this little @geogebra.org animation of mine - shows how the area of a fixed perimeter rectangle changes as we vary the side length.

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thechalkface.bsky.social @thechalkface.bsky.social · 01/10/2025

Rock-Paper-Scissors-Minus-One: what if both players had to reveal what they were about to play in advance? More mathematically interesting than it might sound... youtu.be/Xv7PnN5vVaU

youtu.be

Rock Paper Scissors Minus One - optimal strategy for the Decide Or Die variant

YouTube video by Anthony Clohesy

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thechalkface.bsky.social @thechalkface.bsky.social · 25/08/2025

Using p5js to create an animated version of the 'paceometer' seen in a @rorysutherland.bsky.social talk: youtu.be/Bc9jFbxrkMk. editor.p5js.org/thechalkface...

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thechalkface.bsky.social @thechalkface.bsky.social · 12/08/2025

Using TinkerCad to design a replacement part for my retractable Stanley knife. At this rate, I only need to break another 40 or 50 household objects and the printer will have paid for itself ;)

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thechalkface.bsky.social @thechalkface.bsky.social · 06/07/2025

@sparksmaths.bsky.social Been trying to model your Binomial-not-binomial data with some Terrible Python Code (tm). Any chance I can access your weird data? Simulating different drop-out rates and want to chi-squared against your actual data. I attach a @geogebra.org visual to get your attention ;)

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