Barbara Park, whose children's books starring Junie B. Jones, a 6-year-old dispenser of abundant opinions, Runyonesque wisecracks and dubious syntax, have sold tens of millions of copies and delighted all but the most grammatically puritanical parents and teachers, died Friday at her home in Scottsdale, Ariz. She was 66.
The cause was ovarian cancer, her publisher, Random House Children's Books, said.
Aimed at beginning readers and illustrated by Denise Brunkus, the Junie B. series comprises nearly 30 titles. The books have sold more than 55 million copies in North America, according to Random House, and have been translated into a dozen languages.
Beginning with "Junie B. Jones and the Stupid Smelly Bus" (1992), Ms. Park kept Junie in kindergarten for a nearly a decade, through a string of predicaments set forth in "Junie B. Jones and the Yucky Blucky Fruitcake" (1995), "Junie B. Jones Has a Monster Under Her Bed" (1997), "Junie B. Jones Is Not a Crook" (1997) and other titles.
Then, in 2001, came a watershed moment: "Junie B., First Grader (at Last!)."
Junie's diction is characterized by an imperfect grasp of English grammar: she favors superlatives like "bestest" and "funnest" and past tenses like "runned" and "thinked."
While some parents and educators howled that Ms. Park was leading young readers into a den of syntactic iniquity, the widely prevailing view, as the trade publication Booklist wrote in 2002, was that the books were "sassy, hilarious and insightful."
Barbara Lynne Tidswell was born on April 21, 1947, in Mount Holly Township, N.J. After attending Rider College in Lawrence Township, N.J., she earned a bachelor's degree in history and political science from the University of Alabama.
Ms. Park began publishing children's books in the early 1980s. She soon developed a reputation for handling weighty subjects with a light touch and often bittersweet humor.
Her first published book, "Don't Make Me Smile" (1981), is the story of a 10-year-old boy whose parents are divorcing.