Audio problem: In "We're All in this Together", you can hear either Troy or Gabriella's voice singing background, not matching the others' lyrics, but their lips are moving to the same words as all the others.
Revealing mistake: In the cafeteria scene, when Gabriella slips in the spilled milk, her tray is not only shot up, but tilted as well. However, after the camera cuts back to Gabriella, there is a cup of "sauce" yet it doesn't slide or tip off the tray.
Continuity mistake: In the homeroom scene, Ms. Darbus says "Mr. Bolton, I see that your phone was involved so I will see you in detention." and we see a close-up of Troy with both of his hands resting on his cell phone, with one hand ready to close the phone. The camera angle zooms out, and, instead, we see one hand resting on his lap and one hand holding the phone. (00:10:10)
Continuity mistake: When Gabriella is shown Troy on the laptop, dismissing the musical, she begins to cry. She still has wet tear streaks on her face as she looks out the window, but as "When There Was Me and You" begins, her face is dry.
Continuity mistake: When Troy's mom tells Troy to get ready for the party, his dad gives him the basketball. In the next shot his dad is still holding the ball. (00:01:15)
Continuity mistake: The post-callback basketball scene's countdown clock isn't accurate. If you try counting with it, you'll notice that it reaches 0 by the time that the ball's being passed to Troy.
Continuity mistake: When the cheese fries land on Sharpay, they are all standing right beside the staircase (there are three levels of ledge at the base of the staircase), with Jason and others on the ledge by the banister. Then Sharpay screams. Next shot is of Martha standing atop her table, with the staircase and ledges visible behind them, as they all look to the right, as if Sharpay is farther off in the cafeteria. Problem is that Sharpay, Ryan, Jason, and all the others have vanished, though they all should be right beside that staircase behind Martha's table. (00:43:20)Super Grover