I've always been inspired by Karim, Ginny, and the whole team behind Mathalicious / Citizen Math over the years. Sometimes they've swum with the current, sometimes upstream, but it's always been the current that's changed rather than their values.
What they've made is beautiful. The way they've made it is also beautiful, even if it hasn't been easy. No big VC or private equity backers. But the payoff, for everyone, is that they're actually able to do something bananas like make every lesson free without asking permission. What a gift.
[email protected] (citizenmath.com) just did something wild. The entire library -- every one of their thoughtfully, beautifully crafted lessons -- is now free.
I absolutely love this from @prospect.org. Worth a read (and a subscribe!) prospect.org/2026/04/06/w...
An equilateral triangle inside a regular hexagon. What’s the angle?
#geometrypuzzle