Fold 1
- Ages
- 4–6
- Reading grade
- Pre-K–K
- Stage
- First Reader
- Book
- 6 × 9 in, 24 pp
- Words
- 108
- Words a sentence
- 3.7
- Longest sentence
- 7 words
- Flesch–Kincaid grade
- -2.3
For educators
Six books on one animal, from a child's first book to read alone to popular science for adults. A class can study the same facts with every reader in a book they can manage.
The reading ladder
Measured on each book's reader-facing text with the Flesch–Kincaid formula, the same count the books are checked against before print.
| Measure | Fold 1 | Fold 2 | Fold 3 | Fold 4 | Fold 5 | Fold 6 |
|---|---|---|---|---|---|---|
| Ages | 4–6 | 6–8 | 8–10 | 10–12 | 12+ | 12+ |
| Reading grade | Pre-K–K | K–2 | 1–2 | 2–4 | 4–7 | not graded |
| Stage | First Reader | Read Together | Early Reader | Explorer | Field Guide | Deep Dive |
| Book | 6 × 9 in, 24 pp | 8.5 × 8.5 in, 32 pp | 6 × 9 in, 32 pp | 8 × 10 in, 40 pp | 8 × 10 in, 48 pp | 6 × 9 in, 56 pp |
| Words | 108 | 253 | 504 | 2,164 | 5,356 | 8,904 |
| Words a sentence | 3.7 | 4.4 | 6.8 | 7.5 | 10.8 | 16.8 |
| Longest sentence | 7 words | 11 words | 10 words | 18 words | 26 words | 43 words |
| Flesch–Kincaid grade | -2.3 | -0.5 read aloud | -0.7 | 2.6 | 6.5 | 9.8 |
Fold 2
- Ages
- 6–8
- Reading grade
- K–2
- Stage
- Read Together
- Book
- 8.5 × 8.5 in, 32 pp
- Words
- 253
- Words a sentence
- 4.4
- Longest sentence
- 11 words
- Flesch–Kincaid grade
- -0.5 read aloud
Fold 3
- Ages
- 8–10
- Reading grade
- 1–2
- Stage
- Early Reader
- Book
- 6 × 9 in, 32 pp
- Words
- 504
- Words a sentence
- 6.8
- Longest sentence
- 10 words
- Flesch–Kincaid grade
- -0.7
Fold 4
- Ages
- 10–12
- Reading grade
- 2–4
- Stage
- Explorer
- Book
- 8 × 10 in, 40 pp
- Words
- 2,164
- Words a sentence
- 7.5
- Longest sentence
- 18 words
- Flesch–Kincaid grade
- 2.6
Fold 5
- Ages
- 12+
- Reading grade
- 4–7
- Stage
- Field Guide
- Book
- 8 × 10 in, 48 pp
- Words
- 5,356
- Words a sentence
- 10.8
- Longest sentence
- 26 words
- Flesch–Kincaid grade
- 6.5
Fold 6
- Ages
- 12+
- Reading grade
- not graded
- Stage
- Deep Dive
- Book
- 6 × 9 in, 56 pp
- Words
- 8,904
- Words a sentence
- 16.8
- Longest sentence
- 43 words
- Flesch–Kincaid grade
- 9.8
Using the set with mixed readers
Start everyone on one fact
Open the ladder on the board and pick a fact. Each fold tells the same fact in its own words, so the whole class can talk about it together, whatever they are reading.
Hand out by fold, not by name
Children choose the fold that fits them this week and move up when they are ready. Because the facts match, a group reading different folds can still compare notes.
Climb one rung
A confident reader reads a fact in their own fold, then the next fold up, and tells a partner what the deeper version adds.
Let the youngest listen
Where narration is available, Read to me lights each sentence as it is spoken. It suits pre-readers and children new to English.
Trace a sentence to its source
Older students pick a sentence, find its fact in the fact bank and open the source behind it. It is a short lesson in checking what you read.
Fold by fold
Run, Wolf, Run!
Fold 1 · First Reader · Ages 4–6
What it is for
Read page 3 together first: point to each pictured word, wolf, pack, howl and smell, and say it. These four are set in bold the first time they appear. When your child meets one of them, point back to its picture on page 3. Every other word can be sounded out letter by letter or is a common sight word such as the, is, see and come; help your child sound words out rather than guess from the picture. The age band is a guide, not a promise that every child is ready. Pages 22 and 23 give adults the facts and sources behind each page. For a book to read together, try Fold 2, Hello, Wolf!
Talk about it
Start from a chapter:
- Words to know
- The facts behind the pages
- Pack life and play
Words
- wolf
- a wild dog
- pack
- Mom, Dad and pups
- howl
- a long call
- smell
- to sniff
Hello, Wolf!
Fold 2 · Read Together · Ages 6–8
What it is for
Read aloud and pause for your child to point, answer or join a sound; they do not need to read the words. The sound words are play, not recordings of wolf calls. Packs differ in size and habits, so one pictured family does not show how every wolf lives. When your child starts reading alone, try Fold 1, Run, Wolf, Run!, then Fold 3, Wolf: Voices on the Wind.
Talk about it
Questions the book asks its reader:
- Can you point to the ears?
- Who is in your family?
- Can you close your eyes tight?
- Where do you feel safe?
- Who takes care of you?
- What games do you play?
Words
- wolf
- a wild animal in the dog family
- pack
- a wolf family
- howl
- a long, loud call
- den
- a safe home under the ground
Wolf: Voices on the Wind
Fold 3 · Early Reader · Ages 8–10
What it is for
Read the three pictured words on page 3 together first; each is set in bold the first time it appears in the story. Then let your child read the book to you. Almost every word can be sounded out with the phonics most children learn in first grade. When a word stops them, give them time and help them sound it out; only for the three bold words, point back to the word and its picture on page 3. Arjun and Elena ask questions along the way, pages 28 and 29 ask recap questions, and page 30 has a short quiz with its answers. The book says pack, not alpha, because wolf packs are families, not ranked groups. Children needing shorter text can start with Fold 1, Run, Wolf, Run! Readers ready for chapters can go on to Fold 4, Wolf: A Life in the Pack.
Talk about it
From the book's quiz:
- What is a howl for?
- Does a wolf live alone?
Words
- wolf
- a wild animal
- pack
- a family of wolves
- howl
- a long call
Wolf: A Life in the Pack
Fold 4 · Explorer · Ages 10–12
What it is for
This book is for readers of about 10 to 12 who read on their own. Each chapter opens with a big picture. Then most pages mix short text, a Wow! box, a picture or diagram, and a question from Arjun or Elena. Read a chapter at a time, or start anywhere. Try the quiz on page 36 together. The glossary is on page 37. Page 38, "How we know", shows how scientists found some of these things out. For a gentler read, try Fold 3, Wolf: Voices on the Wind. Ready for more? Try Fold 5, Gray Wolf: A Field Guide.
Talk about it
From the book's quiz:
- Who leads a wolf pack?
- Can newborn wolf pups see?
- How does the pack feed its pups?
- How far can a wolf's howl travel?
- How many smell sensors does a wolf's nose have?
- How big can a wolf pack's territory be?
Words
- den
- An underground room where wolf pups are born.
- dispersal
- When a young wolf leaves its birth pack to start a new family.
- guard hairs
- The long outer hairs that shed water and block wind.
- pack
- A family group of wolves, led by the mother and father.
- regurgitate
- To bring swallowed food back up to feed pups.
- scent mark
- A smell signal left to tell other wolves a territory is taken.
- trophic cascade
- A chain of changes that spreads from a top predator through nature. In Yellowstone, returning wolves helped some willows grow back.
Gray Wolf: A Field Guide
Fold 5 · Field Guide · Ages 12+
What it is for
This guide is for readers of twelve and up. Chapters can be read in any order. Seven labeled diagrams show a wolf's body, pack life, voices, and territory. Every chapter has a Scientist spotlight or a Try it box, and Arjun and Elena model field-notebook questions. The glossary defines technical terms, the index points to topics, and the sources are listed at the back. Discuss what evidence supports each claim. Next, try Fold 6, The Gray Wolf, Unfolded.
Talk about it
Questions the book asks its reader:
- When you spot a wolf, can you note its color, size, and place before anything else?
- Will you put a date and a place at the top of every notebook page, the way I do?
- Why not keep a separate page in your notebook for open questions?
- Found an elk bone cracked open to the marrow?
- Could a wolf's powerful jaws and back teeth have done that?
- Found a track in snow or mud?
Words
- allogrooming
- licking or nibbling another animal's fur to strengthen social bonds
- canid
- a member of the dog family (Canidae), including wolves, foxes, and coyotes
- carnassial
- a shearing tooth that slices meat like scissors
- dichromatic vision
- seeing two color ranges (blue and yellow) instead of three
- digitigrade
- walking on the toes with the heel raised off the ground
- dispersal
- the journey of a young wolf leaving its birth pack to find a mate and start a new family
- guard hairs
- long, coarse outer hairs that repel rain and wind
- keystone species
- an animal whose effects on the ecosystem are much larger than its numbers
- pheromone
- a chemical message that animals of the same species read by smell
- regurgitation
- bringing swallowed food back up from the stomach to feed pups
- rendezvous site
- an open outdoor area where pups stay while adults hunt
- sagittal crest
- a bony ridge on top of the skull that anchors powerful jaw muscles
The Gray Wolf, Unfolded: The Science of a Family Predator
Fold 6 · Deep Dive · Ages 12+
What it is for
Fold 6 is connected popular science for readers of twelve and up and for adults. It retains species-specific evidence and uncertainty, with no child-guide dialogue. The alpha-wolf myth and its retraction receive sustained attention, and the Yellowstone trophic cascade is presented with the caveats current research requires. Notes and references identify the research behind the factual passages. For a shorter route in, with diagrams and a glossary, try Fold 5, Gray Wolf: A Field Guide.
Talk about it
Start from a chapter:
- The Family
- A Pup's First Year
- The Hunt
- Voices and Scents
- The Body of a Runner
- Wolves and the Land
Words
This fold has no glossary or word list.