(Rollercoaster, roll, rollercoaster)
Isabella: Phineas, are you sure this is safe?
Phineas: Of course!
(Rollercoaster, roll, rollercoaster)
Phineas: It's like a leisurely drive around downtown
But it starts with a 3-mile drop straight down
Yeah, now keep your head and hands and feet inside the ride
Not a written rule, but it's strongly implied
Permanecer sentados, por favor
Scream if you want more!
That's right!

Corkscrewin 'round the interstate
With peanut butter and rubber snakes
Clear the way, move over
Look out, Bud
Here comes the mud!
Rollercoaster, roll, rollercoaster
Look out!

Rightside up and upside down
Don't ask me to talk
Can't tell a verb from a noun
And I'm screaming like a baby
Who's afraid of a clown
Buford: I'm glad I'm wearing trousers
That are already brown!
Phineas: It'll twist your melon
It'll turn your gut
Man, is this ride sweet or what?
We go:

Phineas and passengers: Ah ah ah
Ferb: We go:
Phineas and passengers: Ah ah ah
Ferb: We go:
Phineas and passengers: Ah ah ah
Rollercoaster
Buford (on show), Baljeet (on album): I got the poster!
(Rollercoaster, roll, rollercoaster)
(Rollercoaster, roll, rollercoaster)
(Rollercoaster, roll, rollercoaster)
(Rollercoaster, roll, rollercoaster)

http://phineasandferb.wikia.com/wiki/Rollercoaster_(song)