In the scene where Jackson is talking about a giant wiener ruining Miley's operation she is holding a spoon and in another camera shot it's down, but when the camera goes back to the camera shot, less than a split second later, she is holding the spoon the same way.
When Miley is talking to her dad, Jackson is there, but in the next scene, he is gone, but is there again in the scene after that.
When Lily is talking to Miley when she has a lollipop in her mouth, her hands are separated. In the next shot, her hands are close together.
During the scene where Jackson is "Bucky Kentucky" and he is saying Miley is "little miss nobody", you can plainly see that Jason Earles is wearing his wedding ring.