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??

The Sine Rule (ruler for drawing sine waves) - Free 3D Print Model - MakerWorld Download this free 3D print file designed by the_chalkface. A 10cm long ruler designed for drawing a sine wave.  It covers a cycle and a half (from 0 to 540 degrees, or 0 to 3pi), so by starting at th...

makerworld.com/en/models/21...

Something like this maybe amzn.eu/d/7du1AxO

Login - Tinkercad

www.tinkercad.com/things/dJFfk... just made in tinkercad - this should let you download the stl, or adapt it if you like. I'm thinking of doing a few for my classes (maybe let them keep them if they demo questions at the front...)

I made a thing!

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.

Sounds like the start of a simultaneous equations question!

A fractal that splits the unit square into 1/4 + 1/16 + 1/64 + ... = 1/3

The rose curve r = cos(2theta) takes up 1/2 of the space of the unit circle

The cardioid is enclosed within a circle such that the space in the circle but not the cardioid takes up 1/4 of the circle.

A few more obscure ones.

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.

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?

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.

YouTube video by Anthony Clohesy Rock Paper Scissors Minus One - optimal strategy for the Decide Or Die variant

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

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

3D CAD image from TinkerCad

Photo of the broken part

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 ;)

I tried a few things before factoring the LHS and bisecting the asymptotes - I knew I was on the right lines because the numbers all worked so nicely! Well constructed :) how would you go about rotating if you don't already know the angle? I thought of trying it but couldn't see how.

I've used the 'any 4 points... parallelogram ' before - nice vectors proof. Never thought to do this though! Thanks

@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 ;)