History Recap / PhineasAndFerbActYourAge

* SpellMyNameWithAnS: Milly's name is misspelled as "Millie" in the credits.

* TheCameo: Candace only appears briefly as a law school student giving a dissertation to her professors.

** During his mid-life crisis, [[MidLifeCrisisCar Doof purchases and crashes a sports car]], but the car dealer offers him another one, this time in yellow. At the end, Vanessa shows up driving said car, indicating Doof gave it to her off-screen. This in itself is another Brick Joke as Vanessa in [[Recap/PhineasAndFerbVanessassaryRoughness previous]] [[Recap/PhineasAndFerbFindingMaryMcGuffin episodes]] expressed wanting a new car to her father.

* BookEnds: The episode begins and ends with Dan and Swampy [[ArtShift in live action,]] sitting next to a pile of viewer mail.

* TeensAreShort: [[AvertedTrope Averted]], Isabella is as tall as her mom, and the other kids are pretty tall as well.

* AccidentalMisnaming: Irving says that the -inator alert is coming from a "Dr. Dooferdsmits." Doofenshmirtz decides to ditch the Mid-Life Crisis-inator and go back to his slow-paced lifestyle and confirms his bowling plans with Perry.

''Oh, get a grip, Swampy!''

With Isabella's shift at the restaurant done, she says goodbye to her mom and drives away. A chance glance at a photo of Phineas in her wallet causes her to reminisce about all the summers they spent together, and laments at what life might have been like if she and Phineas managed to get together. Similar thoughts roll in the mind of Phineas when he reaches the restaurant too late to see her off. He realizes that, in hindsight, all of Isabella's advances had been extremely obvious and he never took a hint.

Phineas, downcast, eventually reaches Isabella's house, only to see her gone; however, a truck moves away, revealing her on the steps of his house. As the two sit together, Isabella says that she couldn't leave without saying goodbye to Phineas, and they talk. Phineas tells her about the crush, and Isabella admits that she did have a "big crush" on him during their youth, but gave up on it during high school. Phineas, in turn, admits that it is precisely during that time when he started having feelings for her. The two are saddened by the bad timing, but when Isabella mentions she's going to Tri-State State, Phineas makes up his mind and says that he'll be going too. With applause from Baljeet, Buford, Ferb, and the Fireside Girls, Phineas and Isabella hug and begin their relationship, promising to see each other in two weeks.

* ArtisticLicenseUniversityAdmissions: ''WesternAnimation/PhineasAndFerb'' When Isabella is leaving for college, Phineas hasn't decided where ''he's'' going to college. That very same day, he decides to go to the same school as her. In reality, even for schools with high acceptance rates, he would still have had to register and pay tuition months in advance to secure his spot at the school. Additionally, even if he ''did'' already get accepted to that college, he would still have had to accept their offer of acceptance well in advance in order to attend.

* ChekhovsGun: At the beginning, Phineas decides to naturally pick two viable invitations for college: Tri-State State and Danville U. When Isabella reveals that her choice happened to be the same one Phineas got an invitation for, meaning that they can still be together.

* ObliviousToLove: On both ends. Phineas never figured out Isabella had a ''massive'' crush on him for the last ten years until he was flat-out told by his friends, while Isabella remained completely blind to Phineas's affections throughout high school (which were greatly implied to be as obvious as her affections were for ''him''). Further, Phineas' verses of "What Might Have Been" actually [[LampshadeHanging point this out]] with him singing that, looking back, he realizes that she was being quite obvious in her flirtations.

* BorrowedCatchphrase: Phineas greets Isabella with her own catchphrase.

* ContrivedCoincidence:
** A dumpster hooked by Doof's sports car manages to take away the romantic dinner set up by the teens. [[LampshadeHanging Lampshaded]] by Katie "wow, now it's exactly like it was when we were kids!"
** Isabella solemnly reveals to Phineas which college she chose to attend, which happened to be the same one Phineas got an invite to.[[note]] Not really all that contrived, Phineas was accepted into several colleges and had yet to decide which one to pick, making it much more likely that he and Isabella would have an overlap there.[[/note]]

* DistantDuet: "What Might Have Been."

* ObliviousToLove: On both ends. Phineas never figured out Isabella had a ''massive'' crush on him for the last ten years until he was flat-out told by his friends, while Isabella remained completely blind to Phineas's affections throughout high school (which were greatly implied to be as obvious as her affections were for ''him'').
** Phineas' verses of "What Might Have Been" actually [[LampshadeHanging point this out]] with him singing that, looking back, he realizes that she was being quite obvious in her flirtations.

* ShoutOut: "Phinabella", the shipping name of Phineas and Isabella among the fandom, is utilized in the song "What Might Have Been".

* ContinuitySnarl: Carl mentions that Doof gave up evil after being placed as a teacher in Vanessa' high school, as seen in "Doof 101," but in [[Recap/PhineasAndFerbLastDayOfSummer the actual finale]] he gave up being evil after Vanessa pointed out to him that he wasn't really a bad guy at heart. Granted, it's also likely Carl might not be aware of this.

* EveryoneCanSeeIt: By the time of this episode, ''everyone'' is completely aware of the {{UST}} going on between Phineas and Isabella. Heck, even ''Vanessa Doofenshmirtz and Isabella's mother'' knew about Isabella's crush on Phineas! This leads their friends to do everything they can to get them together. It's lampshaded by Vanessa in the end.

* INeedToGoIronMyDog: Dan leaves at the end, apparently embarrassed by Swampy, who was touched by the emotional ending, by saying he's "got a thing".

* AccidentalMisnaming: Irving says that the -inator alert is coming from a "Dr. Dooferdsmits."
* AffectionateNickname: Vanessa calls Ferb "Ferbs" as she meets him at the Flynn-Fletcher house. Averted, as WordOfGod confirms that Ferbs is [[FirstNameBasis his real name]].
* BeYourself: At the end, Doofenshmirtz decides to ditch the Mid-Life Crisis-inator and go back to his slow-paced lifestyle and confirms his bowling plans with Perry.

-->'''Vanessa''': I never knew she had a thing for him.
-->'''Ferb''': Seriously?
-->'''Vanessa''': No, I'm just messing with you. Everyone knew!