u/JimBroIV

The last onscreen appearance of Jimmy Neutron characters(not counting Planet Sheen) was a commercial for the 2010 Chrysler Town and Country minivan and was strangely released several years after the series was cancelled. Voice acted by the original cast for Jimmy, Carl, and Sheen, the models are extremely high definition and are the best the characters have ever looked. Sheens model looks much better than the one from Planet Sheen as well. It’s a very short commercial but is humorous and gives a look what a Season 4 of Jimmy Neutron might have looked like if it was made in the late 00s instead of Planet Sheen.

Chrysler Town and Country Commercial: https://youtu.be/TiMqAc6K2kA?is=fNIDF0J2I9Vm5d4t

The first one was Johnny Quasar!, a 1995 short simply introducing Johnny and his dog Goddard flying on a rocket for less than a minute. His head is much larger than the finished Jimmy Neutron model and afterwards the character was renamed to Jimmy Neutron due to the similarity of the name to Johnny Quest and Captain Quasar.

The second pilot is a more developed 13 minute long one from 1998 called Runaway Rocketboy! which impressed Nickelodeon executives so much that they used the basic premise for the movie. The models look really good for 1998 as well and the character design is mostly the same as the 2001 movie release.

There was also 7 promotional shorts created with the movies rendering engine to promote the movie but were less than 2 minutes each and simple shorts to show on TV as advertisement, not as pilot episodes to pitch to executives. Some of the shorts look similar to Runaway Rocketboy! while later ones are identical to the graphical fidelity of the movie.

Johnny Quasar! short: https://youtu.be/aljsNx0VHKA?is=Aho5kfKi8tGFKl8B

Runaway Rocketboy! pitch: https://youtu.be/hjGuQovZCNI?is=8FA-kCbrbrCv8DaV

Promotional movie interstitials: https://youtu.be/gFYrZ0AFAvM?is=4q8nbUZjU7D1tMCB

Prior to the release of Planet Sheen, there was some very preliminary work on an Ultralord spinoff series. Sadly the series never went that far.