Родилась 11 мая 1927 г. в Калифорнии. С 1964 г. опубликовала 43 книги, из которых три удостоены премии Медаль Ньюбери: The Egypt Game, The Headless Cupid (Ворон, колдунья и старая лестница), и The Witches of Worm.

Библиография:

Game Series
The Egypt Game (1967)
The Gypsy Game (1997)
Supplemental materials - The Gypsy Game Teacher's Guide (1998)

Stanley Family Series
The Headless Cupid (1971) (a.k.a. A Witch in the Family, в русском издании "Ворон, колдунья и старая лестница")
The Famous Stanley Kidnapping Case (1979)
Blair's Nightmare (1985)
Janie's Private Eyes (1989)

Green Sky trilogy
Below the Root (1975)
And All Between (1976)
Until the Celebration (1977)

Castle Court Series
The Box and the Bone (1995)
The Diamond War (1995)
Ghost Invasion (1995)
Secret Weapons[disambiguation needed] (1995)

Gib Series
Gib Rides Home (1998)
Gib and the Gray Ghost (2000)

Other novels
Season of Ponies (1964)
The Velvet Room (1965)
Zilpha Keatley Snyder (1966)
Black and Blue Magic (1967)
Eyes in the Fishbowl (1968)
Today Is Saturday (1969)
The Changeling (1970)
The Witches of Worm (1972)
The Princess and the Giants (1973)
The Truth About Stone Hollow (1974) (a.k.a. The Ghosts of Stone Hollow)
Heirs of Darkness (1978)
A Fabulous Creature (1981)
Come on Patsy(1982)
The Birds of Summer (1983)
The Changing Maze (1983)
And Condors Danced (1987)
Squeak Saves the Day and Other Tooley Tales (1988)
Song of the Gargoyle (1990)
Libby on Wednesday (1991)
Fool's Gold (1993)
Cat Running (1994)
The Trespassers (1995)
The Runaways (1999)
Spyhole Secrets (2001)
The Ghosts of Rathburn Park (2002)
The Unseen (2004)
The Magic Nation Thing (2005)
The Treasures Of Weatherby (2006)
The Bronze Pen (2008)
William S and the Great Escape (2009)
William's Midsummer Dreams (2011)