* ActorAllusion: Taylor makes it quite clear she's attending Yale following high school. Interestingly, Monique Coleman [[Series/GilmoreGirls has already attended]], and she was even on the paper.
* AdoredByTheNetwork: Disney Channel (at least in Australia) once had a tendency to overpromote any of the films if it's set to air within a week. Almost every single commercial will have at least one ad about it. Considering that, at least between 2005 - 2010, the film aired once a month, this was quite common.
** Since 2015, Disney's main movie channel in Australia tends to play the third film every week, and will commonly play songs from the three films between movies. ''Film/{{Descendants}}'' pretty much took the trilogy's place on Disney Channel itself.
* CutSong
** The [[http://www.youtube.com/watch?v=ir38tIOQdT0 Humuhumunukunukuapuaa]] song and scene were cut from the televised version of ''High School Musical 2''. They reinstated it on the DVD and in the stage adaptation.
** There was also a song recorded for the 3rd movie called "Last Chance" that never made it into the movie apart from the reprise in the [[http://youtu.be/wWq9E6JBxCw medley]] of most of the songs in the movie. A [[http://youtu.be/ewpi5_39-Fw 40 second preview]] leaked in 2008 before the movie came out.
** In the first movie, there were a few songs that didn't make the cut. The love song "I Can't Take My Eyes Off Of You" was recorded by the four main leads (kind of {{Squick}}y because [[BrotherSisterIncest two of them played siblings]] and ended up on the album and as a [[http://youtu.be/uSBoARL2N3g bonus music video]] on the DVD (it's made to look like they're all recording the song but Zac Efron is there instead of Drew Seeley [[TalentDouble who did most of the singing for Zac's character]]. It also made it into the play version of the movie a duet between Troy and Gabriella, as did "[[http://youtu.be/ZHXU_wiWb5M Cellular Fusion]]" and "[[http://youtu.be/qJA9BTwmHTs Counting on You]]" but the song between Mrs. Darbus and Coach Bolton seems to be lost forever.
* DawsonCasting: Many of the actors were actually in their early 20s, though when the films initially started, most of the characters were played by people close to their actual age. Taylor's actress, Monique Coleman, was 26 at the time of the first film.
** Averted by Austin Butler in the spin-off film, who was nineteen and playing a college freshman.
*** Likewise [[Series/GoodLuckCharlie Bradley Steven Perry]] as Sharpay's rival.
* FakeAmerican: Oleysa Rulin (Kelsi) is originally from Russia.
** Though she was raised in Texas and Utah and does not have to fake an accent so this trope is debatable.
* FollowTheLeader: The success of HSM led to Nickelodeon's blatant ripoff, ''Spectacular''.
** Their success likely also paved the way for the similar show ''Series/{{Glee}}'', which may have never been picked up without the success of ''High School Musical'', as another musical series - ''Viva Laughlin'' - was canceled after two episodes not long before ''Glee'' premiered.
** And in Britain, to {{ITV}}'s ''Brittania High''.
** Disney also followed themselves with ''Film/CampRock''.
* GenreRelaunch: Disney's first successful live-action movie musical, discounting productions of old musicals, since ''Film/PetesDragon1977'' killed the genre nearly thirty years prior.
* IWantYouToMeetAnOldFriendOfMine: Prior to the first film, Olesya Rulin (Kelsi) and Lucas Grabeel (Ryan) had been in Halloweentown High together, as Natalie the troll and Ethan the warlock, respectively.
* IncestuousCasting: InUniverse. One character remarks that if Sharpay could find a way to play both Romeo and Juliet, Ryan would be out of a job, suggesting that the two have played romantic partners in the past.
* MemeAcknowledgment: For the film's tenth anniversary, Disney XD uploaded Music/BadLipReading's video of selected scenes [[https://www.youtube.com/watch?v=cRvuSPBSPL4&t=757s&index=6&list=FLxe61f5GeKWRoTC9YtTt11w to its official YouTube channel]].
* PlayingAgainstType: Oddly, Ashley Tisdale as Sharpay - her previous Disney role was Maddie in ''Series/TheSuiteLifeOfZackAndCody'', [[HairOfGoldHeartOfGold a completely]] [[NiceGirl different role.]] If you want to go into detail, Ashley basically played a bitchy version of London in these movies.
** Lampshaded in Suite Life of Zack and Cody during the episode "Lip Syncin' in the Rain", where Maddie gets told that she doesn't look like Ashley Tisdale and that she's too nice for the role. She does get the singing role while London lip syncs as her. [[HilarityEnsues Chaos ensues.]]
* RomanceOnTheSet: Between Zac Efron and Vanessa Hudgens, who were together for over five years. They confessed to liking each other during the first film and got together during the second. (Although they hid it for as long as they could to avoid media attention). Kenny Ortega admitted that he'd noticed their chemistry since the beginning, and deliberately paired them during auditions.
* StarMakingRole: For Zac Efron & Vanessa Hudgens.
* ThrowItIn: According to the pop-up edition to the first movie, the scene where Sharpay kicks a bathroom door was ad-libbed.
* WhatCouldHaveBeen: Lucas Grabeel(Ryan) wanted Ryan to be gay (and possibly end up with Chad), but then the MoralGuardians came. This didn't stop "I Don't Dance" from happening though.