1. The rubric High School Musical was initially conscionable a placeholder arsenic Disney and the filmmakers had not yet decided connected a name. 

2. Hunter Parrish and Sterling Knight some auditioned for the relation of Troy Bolton, losing out, of course, to Zac Efrom. However, they would spell connected to prima alongside him in 17 Again, playing his precocious schoolhouse nemesis/daughter's loser fellow and his son, respectively. 

3. Corbin Bleu, meanwhile, archetypal auditioned for Ryan Evans, telling Buzzfeed, "At the time, I didn't cognize astir the relation of Chad Danforth." Once helium landed the role, Corbin really became the idiosyncratic to come up with each of the catchphrases connected Chad's signature graphic t-shirts. "They're successful a container successful my garage," he revealed of Chad's collection.

4. Before going connected to onshore the roles of Sharpay and Taylor, some Ashley Tisdale and Monique Coleman auditioned for Gabriella. "I conscionable knew that I was terrible," Monique said of her Gabriella audition. "I didn't truly consciousness equipped to sing and dance."

5. Lucas Grabeel, meanwhile, archetypal work for the portion of Troy, but knew close distant helium wasn't landing the role: "I went successful close aft Drew Seeley, who ended up singing for Troy successful the movie," helium told Buzzfeed. "I evidently heard him due to the fact that it was successful a trailer, truthful it was truly bladed walls and I was like, ohio shit. I'm wholly not gonna get this due to the fact that that guy's incredible."

6. Oh yeah, successful lawsuit you didn't know: Drew really provided the singing dependable for Troy successful the archetypal HSM movie, which was blended with Zac's arsenic the portion was written for a tenor and Zac is simply a baritone. Drew would spell connected to capable successful for Zac connected the High School Musical tour erstwhile scheduling conflicts got successful the way, but for the follow-up movies, it was each Zac connected Troy's tracks.

"That was a precise immense constituent for me. I had to enactment my ft down and combat to get my dependable connected these tracks," Zac told the Orlando Sentinel. "In the archetypal movie, aft everything was recorded, my dependable was not connected them. I was not truly fixed an explanation. It conscionable benignant of happened that way. Unfortunately, it enactment maine successful an awkward position."

7. According to Rolling Stone's iconic screen story on Zac (aka "The New American Heartthrob"), 1 successful 3 teenage girls successful America really had a poster of him connected their partition (though they cited a random web tract for this factoid). 

8. The sibling rivalry was conscionable arsenic existent off-screen arsenic it was on-screen for Ashley and Lucas...at slightest astatine first. "We were not close. We were not bully friends...we hated each other," Ashley admitted during a video she recorded with Lucas for her YouTube channel. Lucas added that the brace "didn't get disconnected connected the champion foot" erstwhile they started filming the archetypal movie, but yet became adjacent friends. How fabulous!

9. In an interrogation with Buzzfeed, Lucas revealed helium pushed for Ryan's sexuality to beryllium explored aboriginal on. "After speechmaking the script, the archetypal happening I said to [Kenny Ortega] was, 'OK, Kenny, Ryan's gay, right? I cognize it's Disney Channel truthful I'm not truly gonna beryllium gay, but I mean, yeah, right?' And he's like, 'Well, deliberation of it this way: You person the accidental to play a quality who's young, he's into theater, he's an creator and let's spell astatine it from that constituent of view,'" Lucas explained. "He talked to maine astir his ain beingness and helium was like, 'I spot a batch of myself successful Ryan. Yeah, I knew I was cheery successful precocious school, but I didn't archer anybody.' It was astir making it real."

10. Ryan's iconic jazz squares were each Lucas' creation, on with Ryan and Sharpay's vocal warm-up exercises. "It's making amusive of, but besides an homage to 2 antithetic choreographers I had erstwhile I was a kid who would enactment jazz squares successful each azygous number," Lucas revealed. "They ne'er said, 'Everybody loves a bully jazz square,' but it conscionable fit, truthful I wanted to marque it a happening that Ryan wanted to enactment a jazz quadrate successful each number."

11. On the set, Kenny kept a yawn jar, which anyone who yawned had to lend to. "Every twelvemonth for, like, 5 years, connected Christmas helium would donate to a foundation successful our names," Monique said, noting the money went to the Make-A-Wish Foundation of Utah. 

12. After filming connected the archetypal movie finished, Monique returned location to discover an eviction announcement connected her door and was struggling to wage her bills, arsenic was Lucas who had occupation booking different occupation aft the HSM. 

13. After the record-breaking occurrence of the archetypal film, Disney gave fans the accidental to measurement successful connected decisions connected the highly anticipated sequel, including slogans that would look connected Chad's t-shirts, the benignant of sandwiches Troy and Gabriella would devour connected their day and the (very brief) appearance by Hannah Montana prima Miley Cyrus. 

14. Like her on-screen quality Ms. Darbus, the play teacher astatine East High, Alyson Reed helped mentor the kids off-screen too. In fact, she adjacent went connected to go Monique's acting teacher. "She was the idiosyncratic I felt the astir comfy with," Monique told Buzzfeed. "I truly recognition her with helping maine get my assurance back."

15. The 3rd movie successful the franchise was initially intended to beryllium a Halloween-themed diagnostic called Haunted High School Musical, but the concept was yet (and fortunately) dropped, with Zac telling MTV astatine the time, "Yeah, I don't deliberation the haunted happening lasted precise long." The 3rd and last film, the lone HSM movie to deed theaters, was past called High School Musical: Senior Year. 

16. Selena Gomez was astir formed successful HSM 3 arsenic Tiara Gold, Sharpay's caller rival. But, the Disney darling decided to crook down the role "because I didn't privation to bash it," she told the New York Daily News astatine the time. "I program to instrumentality different roles successful acting that are challenging for me. After Disney, I privation to beryllium taken earnestly arsenic an histrion for galore years." Ali Lohan besides reportedly went retired for the relation that yet went to Jemma McKenzie-Brown.

17. Chad's dada appears for the archetypal clip successful the 3rd installment, and Mr. Danforth is played by Corbin's real-life father, David Reivers. (They besides played begetter and lad in Jump In! and Free Style.)

18. Ashley revealed to Buzzfeed that she took location astir each of Sharpay's wardrobe from the archetypal movie, admitting, "Did I deliberation I was going to deterioration them connected the reddish carpet? Probably, astatine the time." And erstwhile Disney tried to yet get the items back, Ashley pulled a Sharpay and said she'd alternatively instrumentality toothpicks into her eyes. "I was like, "No, this is mine.' So they don't person immoderate of the apparel from the archetypal movie. I do."

19. When the archetypal movie came out, fans obsessed implicit which formed members mightiness beryllium dating, with galore reasoning Zac and Ashley were an item. "I retrieve radical reasoning that Zac Efron and I dated, due to the fact that we were connected a batch of mag covers together, due to the fact that we were promoting the archetypal movie," Ashley recalled. "So, we conscionable thought that was truly funny, due to the fact that helium was evidently dating idiosyncratic else, and he's my champion friend."

20. Ah yes, Zanessa. HSM fans had a adjacent meltdown erstwhile it was revealed Zac and Vanessa were a mates IRL. They would spell connected to day for 4 years, becoming 1 of young Hollywood's most beloved couples earlier their divided successful 2010. "It started disconnected truly organically," Vanessa recalled connected THR's Awards Chatter podcast. "I could not person been much grateful to person that narration astatine the time."

21. While they kept it nonrecreational connected the acceptable of the movies, they erstwhile fought during HSM 3. "I retrieve 1 clip we did person a combat and it was portion we were astatine rehearsals," she remembered, "and I retrieve Kenny Ortega coming astir the country with the astir acrophobic look connected his look like, 'Oh no, is our movie going to autumn isolated right?'"

22. In 2016, Disney Channel announced a casting telephone for High School Musical 4, looking for a caller procreation of eastbound High Wildcats to proceed the franchise. Jeffrey Hornaday, who directed Disney Channel hits Teen Beach Movie and Teen Beach 2, was attached to nonstop and choreograph the caller movie, which yet ne'er ended up coming to fruition. 

23. The High School Musical soundtrack was the top-selling medium of 2006, per Billboard, with 3.7 cardinal copies sold, and was the first-ever TV Movie soundtrack to deed No. 1 connected the income chart. 

24. High School Musical 2 is inactive 1 of the highest rated Disney Channel Original Movie of all-time, drafting a whopping 17.2 cardinal viewers. "This was our Super Bowl," Disney Channel president Gary Marsh said astatine the time. "I deliberation we person officially crossed the enactment from High School Musical the movie to High School Musical the mania."

25. With a fund of conscionable $11 million, High School Musical 3: Senior Year grossed implicit $250 cardinal worldwide successful 2008, debuting astatine No. 1 astatine the container bureau successful its archetypal week.