The Jimmy Timmy Power Hour

The Jimmy Timmy Power Hour Trilogy are 3 hour-length Nicktoon crossover specials, set between The Adventures of Jimmy Neutron, Boy Genius and The Fairly OddParents. The first special premiered on Nickelodeon on May 7, 2004. The two sequels, When Nerds Collide! and The Jerkinators!, both aired in 2006.

The Jimmy Timmy Power Hour (2004)
The first TV movie premiered on Nickelodeon on May 7, 2004.

Struggling with his science project, Timmy Turner wishes that he could be sent to the best laboratory in any universe. When his fairy godparents, Cosmo and Wanda, fulfill this wish, Timmy is sent to Retroville, the fictional universe of child prodigy Jimmy Neutron, who's sent to Dimmsdale in Timmy's universe when he activates a magical transporter created by Cosmo and Wanda. As they attempt to return to their respective settings, the characters interact with the various side characters of each other's universe and Timmy becomes romantically involved with Jimmy's classmate, Cindy Vortex. But Timmy's meddling with Goddard, Jimmy's robotic dog, and the seizure of the magical transporter from Jimmy by Mr. Crocker, Timmy's fairy-obsessed teacher, both threaten each character's world in turn.

The Jimmy Timmy Power Hour 2: When Nerds Collide (2006)
The second TV movie premiered on Nickelodeon on January 16, 2006.

Timmy and Jimmy enter each other's worlds for a second time, both wanting to ask Cindy out to their school dance celebrating Friday the 13th. In an attempt to gain Cindy's affections, the two engage in a battle of smarts that sends Jimmy and his friends to Dimmsdale. As Jimmy seeks to prove that Timmy is a fraudulent scientist, Cosmo and Wanda struggle to keep their existence a secret from the people of Retroville. Meanwhile, Professor Calamitous, who is of Jimmy's universe, unleashes a surge of anti-fairies from Fairy World that threatens the rotation of Timmy's Earth. Jorgen von Strangle, the muscular fairy supervisor and enforcer of Da Rules, gets increasingly frustrated by Jimmy's and Timmy's friends and their manipulation of fairy magic.

The Jimmy Timmy Power Hour 3: The Jerkinators (2006)
The third and final TV movie premiered on Nickelodeon on July 21, 2006.

In their third and final encounter, Timmy and Jimmy make amends while trying to defeat the enemies from their own universes—including a monster that they concoct together—while accidentally rejecting their respective friends in the process, including Cindy. Initially, they are unable to make the monster evil enough to fight them properly, but when they succeed, he absorbs Cosmo and Wanda's magic and Jimmy's intelligence, and begins destroying both children's universes.

Overall

 * 1) Both shows being combined with 2D and 3D for the crossover was a great idea.
 * 2) The voice acting from both shows are still good.

The Jimmy Timmy Power Hour

 * 1) Funny moments, such as Timmy breaking the fourth wall by saying that when he first appeared in Retroville, he wonders why he looks 3D (bulgy, as he prefers it). The same thing happened why Jimmy wonders when he first appeared in Dimmsdale why he looks 2D (flat, as some prefer it).
 * 2) Great storylines, where Timmy must shut down Goddard, who Timmy uploaded a destructive video game into, before he destroys Retroville, and while Jimmy must stop Mr. Crocker from taking over Fairy World.
 * 3) The ending of the first crossover was nice, with Timmy apologizing to Jimmy for ruining everything and Jimmy sends Goddard to Dimmsdale for Timmy's science fair project.

When Nerds Collide!

 * 1) The second crossover called When Nerds Collide! was also great, where Jimmy and Timmy fighting over Cindy at the Friday the 13th dance and Professor Calamitous befriending Anti-Cosmo and freeing the Anti-Fairies in the process.
 * 2) Speaking of which, Jimmy, Timmy, Cosmo, Wanda, and their friends must save the world from Professor Calamitous and the Anti-Fairies after they make it Friday the 13th every day, stopping the Earth from rotating anymore. Not to mention that Professor Calamitous being in Jorgen's muscular body due to a mishap from Timmy. Jorgen Von Calamitous then takes Cindy to Retroville and creates the Big Bang Bomb, which would've exploded allowing Calamitous to make a whole new Earth in his image.
 * 3) Jimmy and Timmy steal Cindy back and free Jorgen from Calamitous' control by breaking Da Rules. With help from Jorgen, Cosmo, and Wanda, Retroville and Dimmsdale are split, allowing Jimmy and Timmy to both dance with Cindy.

The Jerkinators!

 * 1) The Jerkinators!, despite the plot being weak, was decent as Jimmy and Timmy do apologize to their friends and Jimmy and Timmy get them back and they make a plan to make Shirley vulnerable, and thus the third special is here instead of the Terrible Shows and Episodes Wiki.

Overall

 * 1) The 3D models on The Fairly OddParents characters look quite ugly and uncanny, even though they made plenty of jokes surrounding it.

The Jimmy Timmy Power Hour

 * 1) Timmy is pretty ignorant in the first special since he was responsible for turning Goddard into a killing machine, though he later makes it up by saving Goddard and apologizing to Jimmy for his actions.

The Jerkinators!

 * 1) The third and final crossover, The Jerkinators!, was still not that great, because of the plot, where Jimmy and Timmy create a villain named Shirley in Dimmsdale and forget about their respective normal friends (Carl, Sheen, Libby, Chester, A.J. and Cindy), making them all jealous. Thankfully, it was still decent, as said in WTR#9.

Trivia

 * Timmy, Cosmo, Wanda, Jorgen, Chester and AJ are the only Fairly OddParents characters to have entered the Jimmy Neutron universe.