The Birthday Nobody Told Us
The idea: dates that share a weekday, and counting on with the sevens taken away.
Read it
Who is in this book
-
Wendel Some dates always share a weekday in a year; find the nearest one and count on in sevens from ShowMath -
Marlow Rehearse, perform, then reveal the reason instead of protecting the mystery from ShowMath -
Danya a child of the Green Asks "how do we know?" -
Modo On a clock you only care where you land; seven days wrap round like a seven-hour clock from ShowMath -
Beto a child of the Green Takes things apart
Every recurring character has a short tune, so you can tell who is on stage before a word is said. The tunes play only when you tap, and the Reading Access sound switch turns them off.
The Honest Page
Which parts of this story are true, stretched or made up?
True
- In 2026, 4 April, 6 June, 8 August, 10 October and 12 December all fall on a Saturday, and 23 October, 19 June and 25 December all fall on a Friday.
- The mathematician John Conway called these shared weekdays 'doomsdays' and used them to work out the day of the week for any date in his head. Source
- 2026 is not a leap year, so it has no 29 February.
Stretched
- Wendel knows the anchor weekday for any year. What we simplified: Knowing it for another year takes a second short calculation from the year's last two digits.
Made up
- The Open Hand troupe and its wagon are made up. Wendel, Modo and Marlow come from ShowMath.
Tell it back
Tell the story in your own words: who was there, what went wrong, and what they found out. Then the second lock on the troupe's trunk goes on your belt.
On your belt: the second lock on the troupe's trunk.
Your belt lives on this device. Nothing is sent anywhere.
Ring the hammer for someone
Pick this book for someone younger. The link carries only the book, and it will wait for them on the Green.