The memorable "Aaaugh!" scream from Peter Robbins as Charlie Brown originated from this film. (Oddly enough, it was also heard from Linus in one scene.) Robbins' scream would become a stock sound effect in almost all subsequent Peanuts specials & movies up to the late 1990s, and is used as a scream, not only for Charlie Brown, but any other available character (excluding Snoopy and Woodstock, who had their own variants).
The main storyline of this movie, involving Charlie Brown's participation in a spelling bee, was taken from a sequence that originally appeared in the comic strip. In that story however, Charlie Brown lost in the first round of the competition, misspelling the word "maze" M-A-Y-S. He later loses his temper at the teacher and is sent to the principal's office; as he waits in the hall, he reflects that the reason he misspelled the word was that when he heard the word "maze," the first thing he thought of was the surname of famed baseball player Willie Mays. This last half of the story had been used in You're in Love, Charlie Brown (1967), when Charlie Brown inadvertently yelled at the teacher for "missing the stupid bus" (after he overslept).
The phrase, "It's Sydney or the bush," was used twice (once by Charlie Brown, and the other by Pig Pen) in the movie, both to describe Charlie's predicament in the spelling bees. The phrase is actually an Australian saying basically meaning "all or nothing," or living an easy life in the city ("Sydney") or a hard life in the Outback ("the bush").
The first of the five theatrical, feature-length Peanuts films. The first four of which were written and overseen by creator Charles M. Schulz.