Don't Fool With a Phantom - S2-E8
Continuity mistake: In Mr. Grisby's house, Shaggy says "what a place to live," and Mr. Grisby is shown to be on the left side of him, Scooby and Velma with the crystal ball on their left. It cuts to a different angle as Velma says "it's a nice place" and Mr. Grisby is suddenly on the same side as the crystal ball with his hand on it. (00:05:30)
Don't Fool With a Phantom - S2-E8
Continuity mistake: Fred is explaining his plan to check out the wax museum and Daphne is standing beside him. In the far shot she is facing him with her hand on her hip. It cuts to a close up of Fred and suddenly she is facing the same direction as him and has her arm down at her side. (00:04:20)
Revealing mistake: After the Ape Man runs up the stairs, Fred presses the button to turn the stairs into a slide. But you can see as he moves his finger to the button, he never touches it. His finger hits the switch above the button. (00:19:25)
Continuity mistake: Shaggy and Scooby stop to play a game of pool. When Scooby looks up and notices the ape head trophy has vanished, he has 4 of the balls by him, including the 6 ball. It cuts over to Shaggy, and he has the exact same set of balls next to him. (00:14:50)
Continuity mistake: Scooby finds a half eaten hamburger in a plate on the floor. When the camera cuts further back to show Shaggy, the plate has moved on the floor, as noted by the lines between boards and the placement of the plate and the spider web on the wall. (00:07:20)
Continuity mistake: When Shaggy makes the joke about living without a smart Ape Man, he's lying on his stomach with his legs in the air behind him. His feet are apart as he relaxes. Then suddenly in the same shot, they just jump close together and then slowly spread back apart. (00:06:50)
Continuity mistake: After Candy and the stunt man quit the movie, Mr. Maxwell says he has to withdraw his job offer to the gang as it's too dangerous. As the gang is shown, Scooby is sitting in front of Shaggy and Fred. It cuts to a close up of him as he gets excited about this, and suddenly Fred and Shaggy have vanished. (00:06:10)
Revealing mistake: Scooby knocks on a trunk and it knocks back. Fred is shown and tells Scooby to open it. But in that shot, Fred's face is so badly drawn, you almost can't even tell it's him if not for the clothes and the voice. (00:05:20)
Continuity mistake: The Ape Man breaks the rope bridge that Scooby is on and it begins to fall. But by the Ape Man, the stakes holding the broken ropes are still in the ground at his feet. Scooby falls down and lands on a root, which bounces him back up where he punches the Ape Man. The stakes and broken rope have vanished. (00:03:50)
Continuity mistake: The camera pans over the filming set and stops on the gang with Mr. Maxwell. There is a van behind them with the Ape Man movie poster on the side. The vinyl piece on the side of the van goes behind the poster and is lined up directly with the orange letters saying "EPI-CENTER FILM COMPANY." It then cuts to a close up of the poster and suddenly it has moved up on the vinyl and become smaller, lined up with the underside of "LOCATION No.2" (00:01:20)
Jeepers It's the Creeper - S2-E3
Continuity mistake: Just before the mask is pulled off the Creeper, Scooby's collar splits into two parts and then changes back again.
Don't Fool With a Phantom - S2-E8
Revealing mistake: When the Wax Phantom first appears on stage, Roger Stevens, the culprit behind the phantom, can be seen at the far right of the stage, even though he should be in the Wax Phantom costume.
Don't Fool With a Phantom - S2-E8
Revealing mistake: When Shaggy has the gang look out the window and tricks them, he is talking and as his jaw moves, an extra layer keeps appearing and disappearing from his nose above the black line of the drawing. (00:17:40)
Don't Fool With a Phantom - S2-E8
Continuity mistake: Fred and Daphne are dancing on stage and Jonny holding a trophy is standing off to the side by a microphone. It cuts to a close up of Jonny, and suddenly he is much closer to the mic, and holding the trophy higher. (00:01:15)
Audio problem: Shaggy and Scooby are walking around trying to find the Ape Man to lure him into the trap. There is a sound and Shaggy says "What's that noise?" It cuts to Scooby who is following him who says "RI ron't row." But his mouth does not move at all when he says this. (00:14:15)
Continuity mistake: The Ape Man puts on a mask of Scooby and pretends to be a reflection. As he is mimicking Scooby's movements, he places his hand to Scooby's and his nails are sticking up. It cuts to a different angle and his hand is in a slightly different position, and his nails vanish. (00:10:05)
Continuity mistake: Right after the car chase when the Mystery Machine crashes into the boat and fishes, when Scooby reaches into the pile of fishes, his arm turns green. When he pulls out the fish, his arm is back to normal. But when he reaches back down it changes to green then back to normal when he pulls out Shaggy.
Scooby's Night With a Frozen Fright - S2-E4
Continuity mistake: Prof Ingestrom's parka is found, then it becomes Prof Wayne's parka.
Scooby's Night With a Frozen Fright - S2-E4
Continuity mistake: A heater on a table disappears then reappears as the gang investigates the room.
What a Night for a Knight - S1-E1
Plot hole: It seems unlikely that: 1. The curator, who's short and chubby could fit into that suit of armor. 2. How he could be strong enough to lift up the table Scooby and Shaggy are hiding under at one point, 3. That the museum has no security guards who might catch the curator and his thugs during their art forgery scheme and 4. There are eyes shown moving in the suit of armor when the gang's talking to the curator despite the fact he's the Black Knight Ghost.
Chosen answer: A ghost wouldn't have to keep any food in the fridge - they don't need to eat. So it is one thing that proves the ghost is not a ghost.