Mathematics
- Unpacked Why Measles Needs Almost Everyone Vaccinated The vaccine piece said a vaccine shows your immune system a wanted poster. But the poster protects people who never saw it, too. Here's the one-line equation that says how many of us need to look. Opens once you've read “A Vaccine Is a Wanted Poster for a Germ”
- Unpacked Why Rain Doesn't Hit Like a Bullet The raindrop poem says rain "can sting, but never cuts you deep", because drag matches weight long before the ground. Without air, a drop from a cloud two kilometres up would arrive at about 700 km/h. Here's the maths of the brake. Opens once you've read “Raindrops Are Not Shaped Like Raindrops”
- Unpacked How to Weigh Pluto Without Touching It The Pluto speech says early guesses made Pluto as big as Earth, and that it kept shrinking. What finally settled it was a smudge on a photograph in 1978, and one line of algebra any student can do. Opens once you've read “Pluto Isn't Sad, and You Shouldn't Be Either”
- Rhetoric Guess How Many Times Your Heart Will Beat A speech arguing that every student should be taught to make good guesses, on purpose.
- Unpacked How to Win the Guess-the-Sweets Jar The heartbeat speech argued that good guessing can be taught. Here's a chance to prove it at the next school fair, with one sum, one number to remember, and a crowd to help you. Opens once you've read “Guess How Many Times Your Heart Will Beat”
- Rhetoric Your Grandmother's Remedies Deserve a Fair Test An argument that checking a home remedy properly is the most respectful thing you can do with it, and that a ship's doctor showed how in 1747.
- Stories How We Found North in a Power Cut The lights went out across the whole campsite, and the only phone with any battery went with them. Our instructor pointed at the sky and asked for our fists.