Sponge Bob

SpongeBob SquarePants isn't trying to be greener than Al Gore, but he may have an advantage in reaching out to kids.

"He's funnier," jokes Steven Banks, the show's head writer.

In "SpongeBob's Last Stand," a special Earth Day episode airing Thursday (8/7c on Nickelodeon), SpongeBob and his friend Patrick learn that a superhighway is planned for Bikini Bottom — and that it's going to cut right through Jellyfish Fields. They start a campaign to stop it, even though everyone else seems to be apathetic or pro-highway.

Watch part of the Earth Day-themed episode

The special, which follows two hours of nature-themed SpongeBob SquarePants episodes, features two musical numbers, including "Give Jellyfish Fields a Chance," a salute to '60s protest songs.

"Sort of Bob Dylan meets John Lennon," Banks tells TVGuide.com.

Banks said the show never set out to teach environmental lessons. "When you entertain someone and make it funny, sometimes you can get a message across," he said. "Not that we're out here to send messages everywhere."

Instead, Thursday's episode goes for laughs with references that range from Gone with the Wind and Apocalypse Now to Tiananmen Square. At one point SpongeBob (voiced by Tom Kenny) faces a humongous excavator, rather than a tank.

Check out photos from SpongeBob SquarePants

"He doesn't give up," Banks observed. "It's like Winston Churchill: Never, never, never quit."