Continuity mistake: Right after Lucy buys her pictures, she walks on the plaza and takes off her coat, carrying it on her arm. When she starts fainting, George catches her and starts carrying her. Both of her arms are in clear sight and the coat is nowhere to be seen. The shot changes, and then her coat is again wrapped around her right arm, squished between their bodies.
Continuity mistake: When Mickey is being interviewed for the yearbook, watch out for students that walk in his opposite direction. There are obvious recycled extras appearing in multiple shots coming from the same direction, such as the blonde with checkered top paired up with a guy in a blue shirt. (00:09:00)