[s1e1] Rollercoaster/candace Loses Her Head -

In the pilot episode of Phineas and Ferb , several "helpful" recurring features and tropes of the series are established:

(the second half of S1E1) specifically features the family celebrating Candace’s birthday at Mount Rushmore, where Phineas and Ferb attempt to carve her face into the mountain as a "helpful" gift, while Candace nearly loses her mind trying to expose them. [S1E1] Rollercoaster/Candace Loses Her Head

: Phineas and Ferb begin their summer by building a logic-defying rollercoaster in their backyard, setting the "big project" template for the series. In the pilot episode of Phineas and Ferb

: Perry the Platypus sneaks off to his secret lair to receive a mission from Major Monogram, marking the first time he foils Dr. Doofensmirtz's "Inator." Doofensmirtz's "Inator

: This episode introduces Phineas’s iconic catchphrase when he notices Perry has disappeared.

: Candace initiates her endless quest to "bust" her brothers by trying to show their mother, Linda, the massive coaster.

: The invention conveniently vanishes just as Linda arrives, a staple "helpful" plot device usually caused by Dr. Doofensmirtz's antics.