Gravity: A Fairy Tale [PDF + eBook + Bonus Story]

A full-length middle grade novel that teaches gravity, orbits and tides inside the story — eighteen chapters, 187 pages, for readers ages 9–12. EPUB and PDF, with a bonus pendulums story.

Read a Sample

Worry was named by a fairy godmother who promptly disappeared and was never seen again — which left her growing up in a castle of fairy-named children who could use magic, while she could not. Her optimistic sister Hope can. Their teacher, Fortitude Knightward ("Fort for short"), is the last remaining Scholar Knight, and after Worry runs away and discovers she'd rather be useful than left out, Fort offers her the role of caretaker of the castle's enchanted objects — which finally gets her a set of keys.

What follows is a story of astronomy towers, sea riddles, a leaning castle, a bottomless pit, an astonishingly judgmental library, a dragon's lair, and gravity itself: what it actually is, how scientists have used it to find things they couldn't see, and what it might mean for a girl who has spent her whole life feeling pulled toward all the wrong things.

Written by Sarah Allen. Edited by Jennifer Murgia. Illustrated in color by Marie Delwart.

If you own Fairy Tale Physics: Books 1–4. Gravity is Book 4 of that collection, and the two are the same book — not a revised edition, not an expansion. The omnibus comes with a PDF of the complete volume, so if you have it, you already have this story.

What's inside the book

• Eighteen chapters across 187 pages of story
• Two short conceptual explainers set between chapters — The Geometry of Gravity, on why circles and ellipses keep turning up, and Using Gravity to Find the Invisible, on how astronomers discovered Neptune without ever seeing it
• Hands-on activities using what's already in the house:
  • An experiment designed to disprove Aristotle — he said heavier things fall faster, and they don't
  • Drawing a true ellipse with string, two thumbtacks and a piece of cardboard
  • Using magnets to find something invisible, which is the same reasoning that turned up Neptune
  • Taking your own tide observations, to see why the tides took so long to explain
  • A pendulums activity with safety notes — work out what does and doesn't change a pendulum's swing, with a stopwatch and a weight on a string
  • The Exploratorium's Falling Rhythm, a musical experiment for feeling what Galileo found
• Free online simulations, linked where they help — the PhET Gravitational Force and Pendulum Lab simulators, GravitySimulator.org (where you can find out what happens if Earth orbits Saturn), and a scale model of the solar system that takes a very long time to scroll through
• A discussion question and two writing prompts — one at the start asking what you already think gravity is, and one at the end that sends you back to your own first answer

Plus a bonus pendulums adventure, with the calculations

Bundled with the book is Abigail's Totally Purposeful, Definitely Not Accidental or Dangerous, Adventure: A Story-Based Pendulums Exploration — a separate illustrated story with two characters from the world of Gravity. Abigail accidentally teleports herself to an unknown underground location, and has to measure the local strength of gravity with a pendulum necklace to work out how to get home.

• The full story, with the math optional — a reader who doesn't want algebra can skip the calculation sections and still follow the plot
• A teacher guide with three adaptations — a No-Math version (ages 8–10), a Medium-Math version (ages 11–12) for students who can put numbers into an equation, and an All-the-Math version (14+) for students ready for algebra
• Activity 1 — Measure the Strength of Gravity Where You Are, a real pendulum experiment
• Activity 2 — Make a Planetary Pendulum Necklace, with a string-length table for every planet in the solar system
• Three sets of practice exercises — a Rearranging Equations Super Challenge, Pendulum Calculations, and "Guess What Planet You're On!"
• A full solutions manual, with every problem worked step by step

What you'll get

• An EPUB of the book — for Kindle, Apple Books or Kobo
• A PDF of the book — for any device, or for printing
• A PDF of the bonus pendulums adventure, with all the activity instructions, the teacher guide and the full solutions manual

All three are ready the moment you check out — the download buttons are on the confirmation page. Your order confirmation email also has a View Order and Downloads button, which takes you back to your order page to download them any time.

Looking for the paperback? Gravity is also sold as a printed book, which comes with these same files. This page is the digital edition on its own.

Part of the Fairy Tale Physics series

Every book in the series is self-contained and they can be read in any order. Readers of Newton's Laws: A Fairy Tale may notice a familiar face turning up somewhere around chapter fourteen.

About the author

Sarah Allen tutored math and physics for twenty years before becoming a full-time writer. She has a physics degree from the University of Washington (graduated with college and departmental honors) and a master's in Cognition and Learning from Columbia. Her goal is to write the sort of physics books she would have wanted as a kid.

Ages 9–12 · 187 pages · Color illustrations · EPUB and PDF · Bonus pendulums story PDF with activities, practice exercises and full solutions