The shows trademark of all the characters having different tongue colors comes from an experience Danny Anntonucci once had, while in a meeting his son and friends came in, due to all the candy they just ate, they had different tongue colors.
According to Danny Antonucci, the characters were based on real people in his life. The personalities of Ed, Edd n' Edy are based on personal traits of himself,
and the activities of his two sons. The cul-de-sac children and the Kranker sisters
were all based on children he grew up with. He also stated that Rolf is strongly based on himself and his cousins, since he was part of an immigrant family, and grew up in a first generation foreign household with different customs and ways of living.
The Ed boys made a brief cameo in Foster's Home For Imaginary Friends.
It was never shown what's under Edd's hat, but in the flash game, Lunchroom Rumble, if Edd wins, he throws his hat in the air. The game is not considered canon though, as it was not made by Cartoon Network.
Nazz's last name is revealed to be Van Fartonschmeer. She is the only character
whose last name was revealed.
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It was revealed in the episode, The Luck of The Ed, that Ed's unibrow can be removed.
Throughout the whole series, only 3 people have managed
to make Ed angry. Those 3 persons are Johnny, Sarah and Eddy's brother.
Paul Boyd, animator on Ed Edd n' Eddy was shot in the head by the police while on his hands and knees. He battled with bipolar disorder and was suffering mental illness at the time he was killed.
The episode, Look Before Your Ed, was dedicated to him.
