Ashley Tisdale who played Sharpay Evans is a natural brunette in real life. 

 Ryan Evans is obviously dyslexic. He had trouble reading that G-O D-R-A-M-A C-L-U-B sign, when some of the Wildcats came to show their support for the school's drama club, and to.Troy, their playmaker, who just joined the drama club himself to be close to Gabriella.

 All the HSM movies were shot on actual location of a real high school at Salt Lake City, Utah. That's a Mormon capital of the world. No wonder they hired Bart Johnson to play Coach Bolton and Troy's dad in HSM. He's a Mormon too.

  Zac Efron's voice was going through some typical male teenager's changing phase when they shoot the HSM1, so it wasn't good enough for Disney back then. That's why they got another guy, Drew Seeley, who did all the singing in that first movie. Zac did all the singing parts all by himself in the sequels, in HSM2 and HSM3.

  Both Zac Efron and Lucas Grabeel are natural blondes. They both dyed their hair later on in life. Zac dyed his hair brown before they started shooting the HSM sequel, HSM2, so his character, Troy Bolton, without any explanation whatsoever became a brunette in HSM2 and stayed that way in HSM3. Lucas Grabeel dyed his hair black recently, in 2021, for his new part and to avoid being identified with his HSM character, Ryan Evans, all the time.

  Corbin Bleu who played Chad Danforth has a natural curly hair, so there was no need for him to wear any wig when shooting the HSM movies. He later cut his hair short.

  There are no Asian American characters in any of the HSM movies. 

  Some actors from HSM movies, like Corbin Bleu, are also professional dancers. Zac Efron is not one of them. Despite all the dancing he did all by himself, it was just a dance choreography, nothing more. That song "I Don't Dance" from HSM2 would be just perfect for Zac, but it's all wrong for Corbin, who's a dancer himself in real life. Zac Efron became interested in making his own music, so now he has two parallel careers. He's not just an actor anymore, but also a musician, and that means he has a great voice after all, if he can sing in real life just like he did in HSM.

  Zac Efron and Vanessa Hudgens were dating in real life when shooting the HSM movies, from 2005 to 2010.Then they broke up and both moved on with their careers and their lives.

  Lucas Grabeel and Ashley Tisdale, the Evans twins from HSM, never dated each other in real life.