This is the theme song for season 3 of The Epic Tales of Captain Underpants. It is sung by Ramone Hamilton and Jay Gragnani as George and Harold, with Nat Faxon performing some vocal elements as Mr. Krupp/Captain Underpants.
George and Harold: So George and Harold make comic books.
George: We're cool. Harold: Me too!
George and Harold: Now they're summering at summer camp and Mr. Krupp is too! Mr. Krupp: Blah Blah Blah Blah...!
George and Harold: Once they used the Hypno-Ring and first they made him dance, then accidentally, kinda on purpose, turned him into Captain Underpants! Captain Underpants: Traa-La-Laaaaaa!
George and Harold: With a snap, he's the captain, flying through the trees, and don't forget when he gets wet, you'll surely feel the squeeze! Mr. Krupp: Blah Blah Blah...!
George and Harold: Put it all together, what could possibly go wrong? Now this is the end of the Captain Underpants song! By George Beard and Harold Hutchins. Captain Underpants: Traa-La-Camp!