* AssPull: The Timmy Turner Loophole, full stop. [[spoiler: Basically, it was created so that Timmy would be allowed to keep his Fairy Godparents even after growing up.]] Even if it was justified [[spoiler: in that Fairy World does owe Timmy big time for saving them on more than one occasion]], it still came out of left field [[ShaggyDogStory and undermined the point of the special, which was to have Timmy grow up.]]
** If you think about it ''really hard'', there is some FridgeBrilliance to it. There is one chapter of an early-season in which time wishes to be a grown-up and turns into 40-year-old-ish man, only to [[BeCarefulWhatYouWishFor discover that life as a grown-up sucks]] [[hottip:*: Moral Lesson: don't rush to grow up]] [[BeCarefulWhatYouWishFor but also that he can no longer ask for wishes]] (since he is not a child). After many failed attempts, he finally manages to be a child ([[CurseEscapeClause at heart]][[hottip:*: He cried helplessly for his parents to rescue him, [[UnfortunateImplications which is some]][[MenDontCry thing only children do]]), so [[StatusQuoIsGod he is able to return to his old self]].
* BrokenBase: Before the movie even aired, many fans reacted in sheer disbelief if not anger. Now that it has aired, some think it's flat-out awful, and some fans [[SurprisinglyImprovedSequel enjoyed it]].
** The sequel was even more broken. Many saw there being no reason for ''another'' movie.
*** Tootie's adult design has torn up the fanbases, especially Tootie fans.
* [[ComplainingAboutShowsYouDontWatch Complaining About Movies You Couldn't Possibly Have Seen Yet]]: Most of the more negative entries on this page were here long before the movie even aired.
* EarWorm: "Lookin' Like Magic"
* FanDumb: People crying that it should be an AlternateContinuity when [[WordOfGod Butch Hartman]] wrote the movie and himself stated that it is a look into the future of the FOP kid's lives.
* HoYay: Between Crocker and Magnate.
* MoralEventHorizon: Magnate [[spoiler: trapping Tootie in a cage and using a remote control to ''zap'' Cosmo, Wanda and Poof and drain their energy]] is bad enough, but [[FromBadToWorse it gets worse]] when he [[spoiler: wishes for a bottomless ball pit that he wishes a random mook and Mr. Crocker down.]]
* NightmareFuel: Hugh J. Magnate's [[spoiler: creepily smiling and giggling evil rabbit]]
* OneSceneWonder: Jason Alexander and Cheryl Hines as human Cosmo and Wanda, much to the disappointment of many who felt they were much better than the CGI fairies with their TV voices that were used through most of the film.
** [[BabysitterFromHell Vicky's]] scenes.
* ScrewedByTheNetwork: The first showing of the movie and the subsequent re-airings; Apparently, even for the first broadcast, they cut some scenes and for the subsequent re-airings they cut out even ''more'' scenes. This is the first time this has happened with the show as even the reruns are shown in their entirety on Nickelodeon.
* ShipToShipCombat: A large percentage of the people complaining and prejudging this movie are simply angered fans of other love interests such as Trixie, Vicky, or Veronica. This is not helped by the fact that the movie makes a point to establish that [[spoiler: [[NegativeContinuity all other prior romantic moments on the show, besides Timmy being kissed by Tootie against his will, simply did not happen, and that Timmy has never truly loved any other girl.]] ]]
** A [[http://www.nick.com/quizzes/grow-up-timmy-turner-quizzes/one-wish-quiz.html character match-up quiz]] on the official Nickelodeon website strongly suggests that Tootie was the mystery mother of Timmy's children at the end of Channel Chasers, adding gasoline to an already white hot fiery debate, or perhaps dousing it with a splash of cold water).
** Although some people just prefer not to think of this movie as the real ending to the series, as well as not taking the quiz seriously since this isn't Butch Hartman himself saying it.
* ShipSinking: See above.
* {{Squick}}: A twenty three year old man acting like a child, even if it is [[spoiler: an act to keep beloved fairy godparents]] is kind of creepy. It becomes even ''more'' creepy when you realize that this ManChild is likely sharing a locker room and bathrooms with [[FridgeHorror other ten year old boys]]
* TaintedByThePreview: There are fans who really dislike the idea of making a traditional ThickLineAnimation series into a LiveActionAdaptation. The few previews that were shown prior to the movie's premiere did little to alleviate those fans' doubts about this project. There are a variety of reasons for this ranging from Avatar: The Last Airbender's live action movie (perceived by people to have been done very poorly)to the fact that there is some ShipSinking along with the fact that Timmy Turner [[spoiler:never grew up and is now a creepy ManChild]] Even though the movie has now aired, the reaction still is mixed about it.
* TastesLikeDiabetes: For those who didn't like the movie (and even for some who did), the ending was this.
** Also, it's a very predictable and ''cliché'' ending.
* TearJerker: [[spoiler:Timmy and the fairies saying goodbye to each other near the end.]]
* UnnecessaryMakeover: The brief flashback to a live-action "young" Tootie is arguably more pretty, and certainly more recognizable to the viewer, than the live-action "adult" Tootie.
* WTHCastingAgency: Some of the cast.