Genius Sheen knew his Brain would explodeHe was smarter than Jimmy and was able to read minds. He also seemed to have some reality manipulation abilities meaning he could've have adapted past that point.
The reason Jimmy's father acts rather dim is almost certainly because he caused himself brain damage by smoking weed.Let's start with the question of how a boy as smart as Jimmy could have a dad as dumb as Hugh. It's genetically impossible, right? Well, maybe it would be impossible if you believed that Lamarck Was Right. But we know that Hugh could have an acquired condition that made him dumb, but still had smart genes to pass on to Jimmy. Still not convinced? Well, I refer you to the episode where Jimmy time-travels back to the time when his father proposed to his mother in the seventies. Jimmy's mom called him by the nickname "Hughby-Dooby." 'Nuff said. And this may not be relevant, but notice that there's only one letter of difference between "Hugh" and "High."
Jimmy's Mom is just as intelligent as he isShe even studied at college but gave it up for - guess who - Hugh. And pie-baking. She has often shown sudden outbursts of scientific knowledge, that even rival Jimmy's.
Jimmy killed the blimp pilot in the election episode.The three candidates were disqualified due to being guilty of blackmail, fraud, and murder- no, wait, operating a blimp on school grounds. Mrs. Fowl didn't want to cause a panick, and Jimmy used his hypno-ray to erase the information from any witnesses' minds. Alternately, goat-kebab boy was guilty of murder, and Mrs. Fowl disqualified Jimmy instead so as not to incure his wrath.
The Nobel Prize judge was part of the Free Energy Suppression Conspiracy.
Sheen is an experiment gone wrong by Jimmy.In one episode, Sheen pretended to be the genius in order to impress someone, and says that Jimmy was a failed experiment. Could the reverse be true? (Also, I don't recall ever seeing his parents.)
Jimmy is a Genius.Carl and Sheen are his Beholden, and the reason everything he invents goes awry/berserk is because of Havoc. The reason he doesn't display typical Genius behavior is that he's unaware of other Genii in the world.
Jimmy will grow up to become a spy in the futureThe episodes featuring Jet Fusion and Professor Calamitus are clues.
Jimmy will grow up to bring The End of the World as We Know It, a Dystopia, or will just stop inventing altogetherAlmost every episodes are a clue. Jimmy's inventions bring much more chaos than the satisfaction of the people. His inventions seem much more immoral to the masses. So Jimmy's fate has two choices: either to stop inventing and do not contribute to the progress of the world, or, he would just keep on inventing and bring chaos and destruction.
Hilgo from "Time is Money" is Cindy in that future.Being so rich, Judy and Hugh Neutron bought Retroville, leaving everyone else in the town extremely poor. Cindy grew depressed and slowly became.... that, and forgot how to speak. Except for the simple grunt "Da!". Hugh, to humor her, gave her a job as Jimmy's ugly, maid, nanny, THING.
Jimmy Neutron has a itty-bitty bit of Klingon in him.Due to his large head, all he is missing is the ridges, dark skin, scary teeth, and the other Klingon traits. Sadly, his heart is not Klingon, for he thinks like a Vulcan.
Mc Spanky's is an actual burger, like one that would be eaten by a real-world humanNicktoons Unite has him interact with SpongeBob. The Movie shows SpongeBob to be very small. So there.
Jimmy Neutron will grow up to be Howard Wolowitz.Why not?
Cindy is a child of AthenaIf we're going by the Percy Jackson continuity, Cindy fits the description of an Athenian to a T. Not to mention she does Tai Chi, a form of martial arts used for battle, she's highly intelligent, exhibits hubris, has many talents in building things, and we never get to see how she spends her summers. The only reason her grades are lower than Jimmy's is because of the ADHD and dyslexia that demigods naturally have.
The Evil Clone planet wasn't actually destroyed.It just looked like it did, instead, it was teleported into an alternate universe where everyone is a doll. The inhabitants began making evil versions of every other living person. Jimmy was forced to have a doctor he knew monitor them, and make sure they didn't try anything funny. Unfortunately, the doc went mad, and soon he grabbed a chicken from the side of the road to watch the folks because he didn't care anymore.
Jimmy still has a bit of hamster left in him after the incident with trading bodies with the hamster.
Jimmy is actually evilHe causes most of the problems in the show. Being the genius that he is, he could foresee any potential issues (or at least have the sense to run tests beforehand). There's an episode where he modifies a restaurant and it ends up flying and melting all other food sources in Retroville. So, yeah, Jimmy deliberately causes most of the problems in the show, so he can be set up as the hero.
The embarrassing bubble picture is from an unmade crossover with SpongeBob SquarePants.In one episode, they briefly saw a pineapple at the bottom of the ocean. Off camera, they must have investigated. Somehow, perhaps with a shrinking device, they went inside. From there, they shared an embarrassing joint freak-out (The cliched "AAH!" "AHH!" See Flushed Away's first trailer for an example.) scene. Somehow, a photo was taken. That photo is the embarrassing scene from Spongebob's Christmas party AND the embarrassing bubble picture from Jimmy Neutron. Fridge Brilliance, anyone?
Judie makes a sexual reference.In the episode where Jimmy's grandma is introduced. Hugh puts stuff in the car for his romantic getaway with Judie. Judie tells him to be careful because he won't be used to her rearranging the furniture if he broke his back. By rearranging the furniture, she meant sex.