Season 2: 2003–2004
In contrast to season one, 22-minute episodes became the norm for season two. There were six episodes with two 11-minute shows, and ten episodes with a full 22-minute show. Also, like episodes 15-16, 18, 19, 20, the theme has an extra sound effect in that same Yokian clip.
| Prod. No. | Title | Summary | Original airdate |
|---|---|---|---|
| 21 | "Sorry, Wrong Era" | Jimmy makes a Time Replay Remote that Hugh uses for the wrong intentions, and accidentally sends Jimmy, Carl, and Sheen back... 200 Million Years! | September 5, 2003 |
| 22 | "The Retroville 9 / Grumpy Young Men" | Jimmy, Carl, Sheen, Cindy and Libby turn into a top-notch baseball team with Jimmy's improved baseball equipment. Absent: Judy/ Jimmy, Carl and Sheen turn themselves into old men to buy an M-rated video game. | October 3, 2003 |
| 23-24 | "Operation: Rescue Jet Fusion" | In a salute to spy films like the James Bond series, Jimmy teams up with his idol, actor and spy Jet Fusion, to save the world yet again from Professor Calamitious. Note: This one hour episode has a special theme at the beginning. |
October 13, 2003 |
| 25 | "Nightmare in Retroville" | Buffy the Vampire Slayer. | October 29, 2003 |
| 26 | "Monster Hunt / Jimmy for President" | A rumor spreads that a lagoon monster will haunt Retroville, but Jimmy thinks otherwise. Absent: Goddard, Hugh, Judy/ Jimmy runs for class president against Cindy and foreign exchange student Bolby, and Carl is being forced by each of them to vote for them. Absent: Hugh, Judy | November 11, 2003 |
| 27 | "Return of the Nanobots" | The Nanobots escape from Jimmy's lab and wreak havoc. | November 14, 2003 |
| 28 | "Holly Jolly Jimmy" | After Jimmy accidentally knocks out Santa Claus (which he originally didn't believe in, due to science.), he goes out to deliver all of the presents. Note: This is the third of three episodes that does not appear in Netflix. | December 8, 2003 |
| 29 | "Love Potion 976/J" | Jimmy creates a love potion for his friends that makes them fall in love with the first person they see. Jimmy falls for Cindy, Sheen for Libby and Carl for Jimmy's mom! | February 14, 2004 |
| 30 | "Sheen's Brain" | Jimmy increases Sheen's brain to be larger and smarter, but Sheen soon becomes evil with his new mental powers. Absent: Hugh, Goddard | March 8, 2004 |
| 31-32 | "The Jimmy/Timmy Power Hour" | Jimmy Neutron and Timmy Turner cross universes. | May 7, 2004 |
| 33 | "Maternotron Knows Best / Send in the Clones" | Jimmy creates a robot version of his mom. Absent: Cindy, Libby/ Jimmy makes clones of himself to escape from chores, but one mischievous clone ruins everything. | May 9, 2004 |
| 34 | "The Great Egg Heist / The Feud" | Jimmy, Carl, Sheen, Cindy and Libby search for a precious egg in a museum. Absent: Hugh, Judy/ Carl and Jimmy are forced to end their friendship as their parents are fighting against each other. Absent: Cindy, Libby | May 10, 2004 |
| 35 | "Out, Darn Spotlight" | Jimmy joins his school play to spend more time with his crush, Betty Quinlan. Absent: Goddard | May 11, 2004 |
| 36 | "The Junkman Cometh" | Jimmy goes to rescue Brobot and his parents from the Junkman's ship. Absent: Cindy, Libby, Hugh (pictured only), Judy (pictured only) | May 12, 2004 |
| 37 | "Foul Bull / The Science Fair Affair" | Miss Fowl takes her students to a rodeo. Absent: Hugh, Judy/ Jimmy is mad that he is banned from the science fair. Absent: Goddard, Judy | May 13, 2004 |
| 38 | "Men at Work" | Jimmy, Carl and Sheen get jobs at the fast food diner, McSpanky's. | May 26, 2004 |
| 39 | "The Mighty Wheezers / Billion Dollar Boy" | Jimmy, thinking the Wheezer family is too nerdy, gives them super powers. Absent: Cindy, Libby, Goddard/ Jimmy meets Eustace, another boy genius who is a rich showoff. | June 7, 2004 |
| 40-42 | "Win, Lose and Kaboom!" | Jimmy, Carl, Sheen, Cindy, Libby, Goddard, and Bolbi compete in an intergalactic game show in order to stop the show from destroying Earth. Note: This movie is also known as You Bet Your Life Form. |
July 9, 2004 |