Continuity mistake: When Sam and Mikaela handcuff all the agents, Sam is wearing a black short-sleeved tee shirt atop a blue long-sleeved tee, before putting on the hoodie. We see the dark tee sticking out when he and Mikaela climb onto Prime. Then moments later, Sam is wearing ONLY a long white short-sleeved (we see it has short sleeves when Bumblebee gives him the All Spark later, through a tear in the hoodie sleeve) tee shirt under his hoodie, when he falls from Prime, when he witnesses Bumblebee's capture and thereafter. (Earlier, after he knocks Mikaela off the moped, from that point on there is a very large hole at the back of his blue and black tees, where we see his skin under the jagged material edges, with no white material seen anywhere. We also see no sign of a long white undershirt at any time when Sam's dark tees go up, during his many action shots.)
Continuity mistake: Odd how Mikaela is not wearing her stud earrings when Sam leaves her to go to Bumblebee and she spots the tow truck across the street, and also when she arrives in the tow truck and says, "Sam, help me with this." Yet, she is wearing them between those shots, when she breaks into the tow truck and hotwires it, and in the prior and following shots. (01:55:25 - 01:57:25)
Continuity mistake: When Banachek shows Secretary Kellar the photo of Blackout from Qatar, the photo is a photo taken of the transformer in the Beagle 2 video. It's not the photo Epps took of Blackout. You can tell because Blackout has a box-shaped body and the transformer in the photo has a slender body.
Continuity mistake: In the junkyard when Bumblebee is trying to get away form the "cop", after Bumblebee locks the doors with Sam and Mikaela inside, the windows continually change from being up and down.
Continuity mistake: When Sam and his parents are being arrested by the Sector 7 officers, inside the house Sam is wearing a blue Strokes t-shirt over a long sleeved shirt. When the shot changes and Sam and his parents are being led in hand cuffs to the police cars, a brown sweatshirt is tucked between Sam's left arm and his back due to the handcuffs. In the next shot, Sam is wearing the brown sweatshirt as he says a line of dialogue. The camera cuts to Agent Simmons of Sector 7, then goes back to Sam, who is now wearing the Strokes shirt and the brown sweatshirt is draped over his left shoulder.
Continuity mistake: In this movie, we see a close up shot of Mikaela's hands in three separate scenes. The first is a shot from behind Mikaela and Sam where they grasp hands and the camera closes in on that. You see Mikaela's short nails, with chipped red polish. The second time we see her hands is a shot where she covers her open mouth with both of her hands in shock. Her nails are unpolished. Finally, the third time is during the ending sequence where both she and Sam have been thrown to the ground near each other. Mikaela stretches her hand toward him, they touch fingertips, and the red nail polish is back.
Continuity mistake: During the final battle, Sam rolls on the pavement and reverses direction as a jet-bot lands and transforms. The next wide shot shows Sam scurrying alongside the passenger-side fender of a black Mercedes sedan as another black car is tumbling over the Mercedes' hood, its doors wide open. This same moment repeats in the next shot, from another angle, but suddenly Sam isn't at the fender of the Mercedes- he has vanished. The angle changes again and the same moment repeats a 3rd time, and Sam is still missing. Then, a closeup shot is looking up past Sam as mayhem rages above, and the black Mercedes he huddles against is suddenly a red car. (02:01:20)
Continuity mistake: During Sam's family genealogy report, when he holds up Captain Witwicky's glasses to show the class, there are cracks in certain areas of both lenses. Those cracks actually change position and characteristics when we see the glasses elsewhere in the film, such as on eBay and when Prime explains their importance to Sam and Mikaela when they first meet. (00:10:15 - 00:17:40)
Continuity mistake: After class when Sam rushes to his father, who is waiting in his car, and tells him that he got an A-, the license plate is affixed to the front bumper. At the start of the next shot, the front license plate is gone, but it then reappears when they arrive at Bobby B's. (00:11:35)
Continuity mistake: In the battle scene with Frenzy in the dam, Agent Simmons uses a flamethrower to push Frenzy away a good distance from the door but in the next shot Frenzy is already halfway through the door.
Continuity mistake: When Jazz uses his magnetic hand to remove some of the guns from the Sector 7 people, the guns fly into his palm, but in the next shot, his hand is down and there are no guns in his hand or on the ground. He couldn't have put his hand down or thrown the guns away that fast between the shots. (01:22:00)
Continuity mistake: In the beginning of the scene where the Decepticon is on Air force One they show a 747 but when they land and they show the Decepticon sneaking off the plane the Air Force One shown is a KC-135. Although you don't see the whole plane, the engines are that of a KC-135, long and slender versus big and round like a 747. Also, you can see the refueling boom, which a 747 does not have.
Continuity mistake: In the city, after Ironhide flips over the missiles that Devastator shot at him, he can be seen falling very close to the ground, but in the next shot, he is much higher up so that he can then shoot himself back up-right.