Continuity mistake: Just after Cory talks about being a "baby shower machine", Morgan walks past him. There's then a quick shot of Alan and then we see Cory again, and again Morgan walks past him. It's not the same shot from two different angles, as Cory is acting differently each time.
Visible crew/equipment: After Amy's C-section Alan walks into the waiting area, and just as his kids gather around him in the wide shot the boom mic dips into view at the top, center of the screen between Alan and the plant (viewed on iPad screen). (00:20:10)
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)
Other mistake: Early in the episode, Amy mentions that she is 7 1/2 months pregnant. This episode takes place around Valentine's Day, which means she would have become pregnant at either the end of June or the beginning of July. However, she revealed she was pregnant around the time Cory, Shawn and Topanga had their senior prom, which would have been around the end of May or beginning of June at the latest, prior to their high school Graduation. So she should be around 8 1/2 months pregnant at the least.
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.