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The Paper Door · ages 6-8

The Hidden Face

The idea: hidden faces — a strip folded the right way keeps a third face inside.

Lan and Inkling step out of a paper door into a college room at Princeton in 1939. Inkling holds Kami. A girl, Rosa, sits at a table with three small drawings and a blank card, and a young man folds a paper strip at the far end.

Read it

One story, three ways: Sprout for a new reader, Grower in short chapters, Reader as a full chapter book. Same plot, same ending.

Who is in this book

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 1939 Arthur Stone, a student from England at Princeton University, found the first flexagon. His new American paper did not fit his English binder, so he cut the ends off and started folding the strips. Source
  • Three of his friends, Bryant Tuckerman, Richard Feynman and John Tukey, joined him. They called themselves the Flexagon Committee. Source
  • Martin Gardner wrote about flexagons in Scientific American in December 1956. People liked it so much that it started his long-running column of mathematical games. Source
  • The three-face flexagon is made from nine triangles in a strip, plus one more to glue. Nine triangles have eighteen sides, and they show as three faces of six triangles each.

Stretched

  • The young man folding strips in our story never says his name. What we simplified: We kept the real Arthur Stone in the background so the children and the cast solve the problem themselves; nobody knows exactly where he sat to fold.
  • In our story his notebook shows the folding drawing for the strip. What we simplified: We drew our own simple folding drawing; we do not know what his own notes looked like.

Made up

  • Rosa, her little brother and the paper door are made up. Kami, Mark, Cornelia, Presso and Crinkle are our own characters.

Tell it back

Tell the story in your own words: who was there, what went wrong, and what they found out. Then a paper hexagon that keeps a third face inside goes on your belt.

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.

Across the Table → For the grown-up: the story in three lines, one question to ask, and one thing to do together.