These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
Big Lipped Alligator Moment:. A perfect example - in the second movie Sharpay tries to get Troy to perform Humuhumunukunukuapua'a with her. What is Humuhumunukunukuapua'a? An extravagant Hawaiian themed number about a pineapple princess and a fish prince falling in love. Characteristic of Sharpay, this is a big production number with three backup dancers and Ryan narrating, providing sound effects/fog, and playing the ocean and fish. Much Narm is involved. And it is never brought up again or acknowledged in the plot. No wonder it was cut from the Disney Channel airings.
That, plus the amazing amount of Hawaiian stereotypes.
Contested Sequel: High School Musical 2. Some saw it as a step in the right direction but there are many who have issues with it, the biggest one being that it's not even set in high school!
Sharpay's Fabulous Adventure. It's not a musical, and even factoring that and it's spin-off status in it has a completely different "feel" to the other movies. And those are the minor points - it forgets that Sharpay was supposed to go to the University of Albuquerque after graduation and that Ryan and Kelsi went to New York (they had to rush just to get Lucas Gabreel into the movie at all, so much that his scene is only in the broadcast version).
Designated Villain: Some people feel this way about Sharpay and Ryan, at least in the first movie. They have been doing all this musical extravaganza for most of their life and then in waltzes two people who have never actually sung seriously a day in their life and they easily got shooed in to get the parts. Although they can be pretty mean at times (especially Sharpay) you can at least understand why they would be pissed off.
Double Standard: Debatable, but it is rather prominent how Gabriella is the one always ending the relationship with Troy. One has to wonder if the reaction would be different if it was Troy singing the tragic break-up songs...
The guys from Rifftrax pointed out how "hilarious" it was intended to be for the female drama teacher to walk through the boys' locker room, implying that if the genders had been reversed it would have been much different.
Imagine if the plot of the second film followed a guy stalking Gabriella, getting his personal assistant to turn her friends and Troy against her, invading her personal space so much it borders on sexual harassment (with his parents basically cheering him on), emotionally manipulating her when she expresses her discomfort with his behavior and holding potential scholarships over her head on condition she'll date him, knowing she's desperately worried about affording College.
In "I Want It All", he joins the kick line with the pink haired cat girls.
A new post-credits scene featuring him cameoing was added to the TV broadcast of Sharpay's Fabulous Adventure.
He wrote and performed the song playing in the car as Sharpay and Ryan drive to Lava Springs in the beginning. How the hell is he not more well known? He's fucking epic.
Tiara in the third movie got a lot of fans when she managed to manipulate Sharpay. Let me repeat that. A freshman managed to keep up a sweet and nice facade for a whole year, and then manipulate the Alpha Bitch and stab her in the back.
Miley Cyrus is among the dancers in the closing number of High School Musical 2. She gets a very brief closeup towards the end. It is, as of 2013, her only appearance in a Disney Channel Original Movie outside of the Hannah Montana franchise.
Fridge Logic: A reason why Humuhumunukunukuapua'a was cut - Sharpay and the other Evans' would be begging Troy to stay at dinner in the scene immediately before it, but Sharpay and Ryan would have had to leave immediately after to change/get to a completely different part of the club.
Ho Yay: Everything about the "I Don't Dance" sequence in HSM 2. When we see them next, they've switched clothes.
Mary Sue: Gabriella is a gorgeous and brilliant new girl in school who immediately attracts the big man on campus and lands the leading role in a school play because of her stellar singing ability.
However this does get worse as time goes on, as in the first film she's a Shrinking Violet with terrible stage fright, has no friends from moving around so much and no apparent hobbies outside of studying until she tries singing. In later movies however she becomes more outgoing and confident, suddenly turns out to be a trained in life guarding, first aid etc. and becomes super-popular.
Troy falls into this too: Very attractive, great at almost every sport, so good at singing/theater he's put up for a scholarship at Julliard with zero training and the most popular guy in school. However both of them are somewhat saved by being a Broken Ace, not happy with the pressure on them and aware their popularity vanishes the moment they fail and let people down.
Narm: It's practically impossible to watch "Bet On It" without at least cracking a smile.
"The Boys Are Back" from the third movie.
Most of Sharpay and Ryan's numbers throughout the franchise, though it's intentional/in-character ie. Humuhumunukunukuapua'a, which is about 3 minutes of pure, undiluted Narm. And subsequently one of the funniest moments in the entire franchise.
Narm Charm: The series in a nutshell. It's ridiculous, corny and twee...but it was insanely popular for a reason.
Surprisingly Improved Sequel: Between a better budget, more production time and the adorable chemistry Troy and Gabriella have developed through Zac and Vanessa's Romance on the Set, Senior Year is probably the best of the three films. Not to mention Troy and Gaby's relationship gets some depth, as per their confiding in each other about their fears for the future.
Each sequel got better in terms of budget and production, with the first one looking much less cinematic than the third.
Special Effect Failure: The second movie, during the song "Bet on It", has Troy looking into the water of a pond, showing his reflection. Ignoring the obvious CGI effect, the reflection itself was not mirrored.
Squick: Off-screen, but...in the first movie, a character says brother and sister Ryan and Sharpay played the title roles of Romeo and Juliet. The kissing scene.
The fact that they, and the theatre director, seem to have no issue with a brother and sister playing romantic interests.
Strangled by the Red String: In a badly-made excuse to stop the rumors that the character is gay, Ryan was paired up with Kelsi in the third movie. They are good together, if you ignore the fact Kelsi was paired with Jason in the first two movies.
Unfortunate Implications: Did anyone else think that "neanderthal evolution" speech Taylor delivers was more than a little bit Nazi? The fact that she's black is doubly ironic.
Troy and Chad stealing the freshmen's clothes in the third movie. The hazing is Played for Laughs.
Wangst: Vanessa Anne Hudgens seemed to be contractually obligated to give the audience one overly emotional break-up ballad. Later, Zac Efron became obligated to supply one token emo, Narmy song per movie, famously including "Bet On It" consisting of Zac Efron interpretive-dancing angstily through the golf course in what's supposed to be a serious moment.
NO, NO, NO NOOOOOOOOOOOOOOOOOOOOOOOOOOOOO. STICK TO THE STUFF YOU KNOOOOOOOOOOOOOOOW.