Which Nickelodeon cartoon aired 'SpongeBob's Last Stand' for Earth Day 2010?

SpongeBob SquarePants aired “SpongeBob’s Last Stand” for Nickelodeon’s Earth Day 2010 programming. The episode debuted in the United States on April 22, 2010, as part of the network’s environmental-themed celebration.

In the story, SpongeBob and Patrick discover that the Shelly Super Highway is planned to run through Jellyfish Fields. They protest because the construction would pollute and destroy the habitat, eventually persuading the people of Bikini Bottom to help remove the highway.

The episode was the eighth episode of the series’ seventh season and the 134th episode overall. It was written by Aaron Springer, Steven Banks, and Derek Iversen, with animation direction by Andrew Overtoom and Tom Yasumi. Nickelodeon paired the premiere with a two-hour marathon of nature-themed SpongeBob episodes.

The title can cause confusion because it sounds like a standalone Earth Day special rather than a regular series episode. It is a SpongeBob SquarePants episode presented as part of the network’s Earth Day lineup—not an episode of another Nickelodeon cartoon such as Rugrats or The Fairly OddParents.