Continuity mistake: When the noir version of Shawn is asking Topanga what she's running from, the pot of coffee is next to his left arm near the edge of his side of the bar, and the coffee mug is slightly to the left of the crease in the bartop. When the shot changes after she asks him what he means, the mug is now directly over the crease, and the pot is in the center of the bar between the two of them. (00:06:53)
Continuity mistake: When Topanga gets sucked into the time continuum vortex, you can see a teddy bear between the skis and a pair of shoes. When the shot changes to Cory, you can see the skis and the pair of shoes, but the teddy bear is now missing. (00:04:03 - 00:04:33)
Continuity mistake: When Cory is telling Topanga that he wants to be sure Wile E. Coyote will be all right, you can see a single piece of popcorn on the right side of the microwave stand in the background. When the camera switches back to Cory after Topanga assures him he's always all right, the piece of popcorn is now gone. The amount of popcorn on Cory's shirt also decreases in both aforementioned shots. (00:02:15)
Continuity mistake: When Eric purchases Rachel's tank top, the placement of his right hand while holding it changes when he says "I'm a collector." (00:10:43)
How Cory and Topanga Got Their Groove Back - S7-E18
Continuity mistake: When Eric sneezes on Jack's cereal, Jack is holding the carton of milk level with his abdomen. When the shot changes, he has already set the carton down on the counter. (00:04:30)
How Cory and Topanga Got Their Groove Back - S7-E18
Continuity mistake: When Eric is saying to Jack "It was you all along," he points his left-hand index finger at Jack, who is shown writing down the lottery numbers Eric provided him. When the shot changes, Eric is now pointing with his right hand, and Jack's hands are suddenly on his hips. (00:16:40)
She's Having My Baby Back Ribs - S7-E17
Continuity mistake: When Alan remarks that Amy never got her figure back after she gave birth to Eric, her arms are folded. When the shot changes, her arms are down at her sides. (00:10:10)
She's Having My Baby Back Ribs - S7-E17
Continuity mistake: After Cory says "You don't have to tell me that" after Shawn compliments his waffles, Shawn is shown holding the fork pointed down towards the waffles. When the shot changes, he is suddenly holding holding the fork perpendicular to his body. (00:04:35)
She's Having My Baby Back Ribs - S7-E17
Continuity mistake: When Jack, Rachel and Angela start heading to their class, a shot of Topanga shows her holding a slice of pizza slightly raised from her plate. When the shot changes, she is suddenly holding the pizza several inches above the plate. (00:01:04)
Seven the Hard Way (2) - S7-E16
Continuity mistake: When Topanga joins the group hug, the piece of paper that Eric wrote on is underneath her. When Cory joins in, the paper has disappeared. It then reappears when Mr. Feeny dismisses everyone. (00:20:10 - 00:20:45)
The War (1) - S7-E15
Continuity mistake: After Rachel sprays water all over Cory, the amount of wetness on his shirt varies throughout the scene. (00:05:53 - 00:09:05)
I'm Gonna Be Like You, Dad - S7-E14
Continuity mistake: When Topanga, Shawn and Angela are hanging out in Cory and Topanga's dorm anticipating Cory's return from the doctor, the slice of pizza that Angela is eating goes from having a small bite taken out of it, to being halfway gone, and back to having one bite taken out of it. (00:12:07 - 00:14:02)
Continuity mistake: When the voice on the intercom is saying "Paging Dr. Chocolate Pudding," Cory's right hand is on Topanga's right arm, and her hands are in her lap. When the shot changes, both of his hands are suddenly resting on his stomach, and her right hand is suddenly resting on his left leg. (00:07:23)
Continuity mistake: When Shawn stands up on the chair to propose a toast, Eric is at his 9 o'clock. When shot changes, Shawn has instantly rotated his body so that Eric is now at his 6 o'clock. (00:16:47)
Continuity mistake: When Morgan is telling Topanga that she wouldn't use her bridesmaid's dress to wipe her ass, she gets cut off by Alan who covers her mouth with his left hand and then begins dragging her out of the reception hall. When the shot changes, he is covering her mouth with his right hand. (00:17:22)
Can I Help to Cheer You? - S6-E18
Continuity mistake: When Tommy is saying to Eric "We've been hanging out with each other for a long time now," Eric's coffee mug is mere inches from his face. When the shot changes, the mug is almost set down on the table. (00:00:58)
Continuity mistake: When Morgan emerges from the kitchen after Topanga picked her up from school, a wall is visible behind the door leading to the kitchen, even though the kitchen itself should be visible. (00:02:18)
Continuity mistake: After Eric smears his hands all over Topanga's face, the amount of skin cream on her right cheek drastically decreases when she is telling Cory she's going to go wash her face. (00:14:35 - 00:15:00)
We'll Have A Good Time Then - S6-E13
Continuity mistake: The picture Rachel takes of Shawn, Jack and Chet is not consistent with the framed picture Jack receives. When Rachel takes the picture, Shawn's necklace is sticking out of his shirt collar slightly and positioned to the right and he has a lock of hair draped over his forehead on the left side of his face. In the framed picture, his necklace is protruding from his collar more prominently and positioned to the left, he has no lock of hair over his forehead, and his left hand can suddenly be seen on Chet's left shoulder. Additionally, the framed picture shows Chet with his head slightly tilted back and showing his teeth as he smiles, but when the picture was taken, his head was level and he only had a slight grin with no teeth showing. (00:04:49 - 00:21:10)
Santa's Little Helpers - S6-E11
Continuity mistake: When Shawn and Angela are talking in the student union building, Shawn's scarf is draped around his neck in an asymmetrical fashion, with the left side shorter than the right. When they sit down on the couch, he pulls the two sides to a symmetrical length. Throughout the rest of the time Shawn remains seated on the couch, the two sides alternate between being symmetrical and asymmetrical. (00:15:20 - 00:16:47)
Answer: Topanga's middle name is never specified. Considering her sister's name is Nebula Stop-the-war Lawrence, Topanga's is probably something equally unusual.