A live-action movie was planned as early as 1997, right before the first book was published, and would have starred Chris Farley. The project was scrapped after Farley died.
According to director David Soren, in an early draft of the film there was going to be a small scene that confirms the Fanon theory that Edith is an Alien.
In an interview, David Soren mentioned that in an earlier draft of the film, there was going to be an homage to Magnolia during the scene where George and Harold are separated, and it was going to have "all the main characters from Krupp, to Poopypants, to Melvin, to the gardener outside the school mowing the lawn, having a little refrain. They all sang about how they were feeling unsatisfied by their current situation, and lonely". Ultimately, the scene just didn't work with the flow of the film, and was cut.
In one of the earliest drafts of the script, before David Soren took over as director, there was going to be a subplot about Harold starting to hang out with "the cool kids", causing a rift between him and George. Thankfully, the filmmakers quickly realized that this subplot did not work at all (mainly due to it being extremely out of character for George and Harold), and it was cut.
On Instagram, Ian Abando (one of the movie's storyboard artists) posted a 3-partseries ofstoryboards regarding this deleted subplot. George sneaks into the Jerome Horwitz's first ever school dance, planning to pull a prank with water balloons, but sees Harold hanging out with the cool kids. He then overhears Harold say that while he's his best friend, he thinks he's "holding onto his youth". This angers him, and he retaliates by launching the water balloons he brought on the entire dance, the cool kids especially. After all is said and done, George walks out holding a boombox over his head playing Queen's "We Are the Champions". Harold, giving in to peer pressure, calls him out for pulling something so immature, which was most likely going to lead to a Plot-Mandated Friendship Failure.
Cool Girl: That was totally lame. Kid 1: Totally. Kid 2: Lamest thing ever. Kid 3: What are you, in nursery school? Harold: (nervously looks at the crowd, then at George) Yeah… what are you… a… baby?? George: (looks shocked and hurt for a moment, then angrily throws down the boombox) You're the baby— (gets right up in Harold's face) —BABY!!!
Early information about the movie had Dr. Diaper, the Big Bad of the first book, as a secondary antagonist.
Some old storyboards revealed that Edith's name was originally going to be "Doris".
Instead of just separating them no matter what, Mr. Krupp was initially going to give the boys an "option B" in which they would have to slave after him, all the while Mr. Krupp taunted them with the Tattle Turtle. George and Harold of course took option B. This plot point was taken directly from the first book, but it was eventually scrapped.
Mr. Krupp was originally going to meet up with the school board to approve George and Harold being separated. He tried to show them the video of George and Harold messing with Melvin's invention as proof of the havoc they wreck upon the school... only to reveal that Harold switched the video out with Purple Dragon Sing-A-Long Friends. While the filmmakers thought the scene was really funny, it was cut because they felt it didn't advance the plot in any way, plus it didn't make sense that Principal Krupp would need anyone to approve him switching two students classes.
Also, judging by the same animatic, it appears the Tattle Turtle was originally going to be in the shape of a teddy bear.
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