Hey Ferb

 is performed by Phineas during the introduction of "Rollercoaster: The Musical!". First acknowledged by Dan Povenmire at the Phineas and Ferb Comic Con Panel (July 2010), it is one of the many musical numbers that appear in the special.

Lyrics
Phineas: I know what we're gonna do today,

though it might sound just a bit cliché.

We can build a rollercoaster, but this time with songs and dancing!

'Cause when we're back in school come next September,

And they ask us, we can both remember

Every cool and clever thing we did all summer long, and glancing

back we're gonna be so glad that we

didn't sit all day and watch TV,

I don't think anyone can disagree

the world is possibilities

And that's what makes me say: Phineas and Chorus: Hey Ferb!

Phineas: Hey Ferb, I know what we're gonna do today

Hey Ferb, I know what we're gonna do today

Hey Ferb, I know what we're gonna do today!...

Phineas and Chorus: Hey Ferb!

Background singers: Boredom is something up with which I will not put

Phineas: Hey Ferb, I know what we're gonna do today

Hey Ferb, I know what we're gonna do today

Hey Ferb, I know what we're gonna do today!...

Phineas and Chorus: Hey Ferb!

Phineas: Hey Ferb, I know what we're gonna do today

Hey Ferb, I know what we're gonna do today

Hey Ferb, I know what we're gonna do today!... Background singers: Boredom is something up with which I will not put

Phineas and Chorus: Hey Ferb!

Phineas: Hey Ferb, I know what we're gonna do today

Hey Ferb, I know what we're gonna do today

Hey Ferb, I know what we're gonna do today!

Hey Ferb!

Background Information

 * Throughout the accompanying video, Phineas and Ferb parody well-known musicals. This encompasses Cats, The Phantom of the Opera, Oklahoma!, Singin' in the Rain, Fiddler on the Roof, West Side Story, The Music Man, Les Misérables, The King and I, Chicago and finally, Cabaret.
 * During the final part of the song, the background chorus repeats the phrase "Boredom is something up with which I will not put." Besides being a direct quote from "Rollercoaster," this line plays on a famous quip attributed (possibly apocryphally) to Winston Churchill: "Ending a sentence with a preposition is something up with which I will not put."