It's About Time! (Part 1 & 2) - S1-E21
Other mistake: Near the end of the episode after they get back, when the camera zooms in on Phineas and Isabella, Isabella's face is gone - only her eyes remain, but after the camera zooms out her face is back.
Phineas and Ferb (2007)
1 mistake in It's About Time! (Part 1 & 2)
More quotes from Phineas and Ferb
The Fast and The Phineas - S1-E4
Trivia: Jeremy mentioned that one of the cars' name was Billy Ray, making a reference to Hannah Montana , which country singer Billy Ray Cyrus stars in Mitchell Musso who played the voice of Jeremy also stars in Hannah Montana.
Answer: "One boring day, Phineas recognizes an important truth; Summer vacation will end, and the teachers will want to know what they did on their summer vacation. And with these two kids, it has to be something extravagant..."http://uk.imdb.com/title/tt0852863/.
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