Other mistake: When Tiara hands Sharpay the bag with the latte you can see that there is nothing in the bag, especially at the end of the scene when Sharpay tosses the bag behind her back. It would have spilled if there really was a latte in there.
Other mistake: When Harry Bright and Sam Carmichael are standing on the dock in Greece after missing the boat, Harry pulls out his invitation and references the wedding in the invitation, but the envelope is sealed. (00:08:20)
Other mistake: During Connect 3's performance at Beach Jam, Nate's guitar is missing its fourth string tuning key, which suddenly reappears as soon as he leaves the stage.
Other mistake: At the beginning of the song "Bloodbath", the newspaper that The Graverobber is holding is headlined, "GENECO IN OPERA FUED". (01:07:35)