After graduating high school, Sachar attended Antioch College for a semester before transferring to University of California, Berkeley, during which time he began helping at anelementary school in return for college credit.^[3] Sachar later recalled,

Sachar graduated from UC Berkeley in 1976 with a degree inEconomics, and began working on Sideways Stories From Wayside School, a children's book set at an elementary school with supernatural elements. Although the book's students were named after children from Hillside and there is a presumably autobiographical character named "Louis the Yard Teacher,"^[3] Sachar has said that he draws very little from personal experience, explaining that "....my personal experiences are kind of boring. I have to make up what I put in my books."^[4]

Sachar wrote the book at night over the course of nine months, during which he worked during the day in a Connecticutsweater warehouse.^[3] After being fired from the warehouse, Sachar decided to go to law school, around which timeSideways Stories From Wayside School was accepted for publication. The book was released in 1978; though it was not widely distributed and subsequently did not sell very well, Sachar began to accumulate a fan base among young readers.^[5] Sachar graduated from University of California, Hastings College of the Law in 1980 and did part-time legal work while continuing to write children's books.^[6] By 1989, his books were selling well enough that Sachar was able to begin writing full-time.^[3]

Sachar married Carla Askew,^[7] an elementary school counselor, in 1985. They live in Austin, Texas, and have a daughter, Sherre (b. January 19, 1987). Sachar has mentioned both his wife and daughter in his books; Carla was the inspiration for the counselor in There's a Boy in the Girls' Bathroom (1988),^[3] and Stanley's lawyer in Holes.